diff --git a/changelog/fix-method-title-availability b/changelog/fix-method-title-availability
new file mode 100644
index 00000000000..d9d2a0c0217
--- /dev/null
+++ b/changelog/fix-method-title-availability
@@ -0,0 +1,4 @@
+Significance: minor
+Type: fix
+
+Set payment method title once title is known.
diff --git a/changelog/fix-tokenized-cart-multiple-variations b/changelog/fix-tokenized-cart-multiple-variations
new file mode 100644
index 00000000000..5d155cd5513
--- /dev/null
+++ b/changelog/fix-tokenized-cart-multiple-variations
@@ -0,0 +1,5 @@
+Significance: patch
+Type: fix
+Comment: fix: tokenized cart & multiple variations.
+
+
diff --git a/changelog/fix-tokenized-cart-subscription-signup-fee b/changelog/fix-tokenized-cart-subscription-signup-fee
new file mode 100644
index 00000000000..5abe9f0226b
--- /dev/null
+++ b/changelog/fix-tokenized-cart-subscription-signup-fee
@@ -0,0 +1,5 @@
+Significance: patch
+Type: fix
+Comment: fix: tokenized cart subscription signup fee price
+
+
diff --git a/changelog/update-5002-authorizations-improve-message-shown-to-merchants-when-there-is-an-error-capturing-authorizations b/changelog/update-5002-authorizations-improve-message-shown-to-merchants-when-there-is-an-error-capturing-authorizations
new file mode 100644
index 00000000000..b76d70e1cf9
--- /dev/null
+++ b/changelog/update-5002-authorizations-improve-message-shown-to-merchants-when-there-is-an-error-capturing-authorizations
@@ -0,0 +1,4 @@
+Significance: patch
+Type: update
+
+Update error messages for payment authorization actions to provide more specific and user-friendly feedback.
diff --git a/client/data/authorizations/actions.ts b/client/data/authorizations/actions.ts
index 0eaf50f105d..0885da1cbfe 100644
--- a/client/data/authorizations/actions.ts
+++ b/client/data/authorizations/actions.ts
@@ -19,6 +19,51 @@ import {
 import { STORE_NAME } from '../constants';
 import { ApiError } from 'wcpay/types/errors';
 
+const getErrorMessage = ( apiError: {
+	code?: string;
+	message?: string;
+} ): string => {
+	// Map specific error codes to user-friendly messages
+	const errorMessages: Record< string, string > = {
+		wcpay_missing_order: __(
+			'The order could not be found.',
+			'woocommerce-payments'
+		),
+		wcpay_refunded_order_uncapturable: __(
+			'Payment cannot be processed for partially or fully refunded orders.',
+			'woocommerce-payments'
+		),
+		wcpay_intent_order_mismatch: __(
+			'The payment cannot be processed due to a mismatch with order details.',
+			'woocommerce-payments'
+		),
+		wcpay_payment_uncapturable: __(
+			'This payment cannot be processed in its current state.',
+			'woocommerce-payments'
+		),
+		wcpay_capture_error: __(
+			'The payment capture failed to complete.',
+			'woocommerce-payments'
+		),
+		wcpay_cancel_error: __(
+			'The payment cancellation failed to complete.',
+			'woocommerce-payments'
+		),
+		wcpay_server_error: __(
+			'An unexpected error occurred. Please try again later.',
+			'woocommerce-payments'
+		),
+	};
+
+	return (
+		errorMessages[ apiError.code ?? '' ] ??
+		__(
+			'Unable to process the payment. Please try again later.',
+			'woocommerce-payments'
+		)
+	);
+};
+
 export function updateAuthorizations(
 	query: Query,
 	data: Authorization[]
@@ -165,17 +210,29 @@ export function* submitCaptureAuthorization(
 			)
 		);
 	} catch ( error ) {
+		const baseErrorMessage = sprintf(
+			// translators: %s Order id
+			__(
+				'There has been an error capturing the payment for order #%s.',
+				'woocommerce-payments'
+			),
+			orderId
+		);
+
+		const apiError = error as {
+			code?: string;
+			message?: string;
+			data?: {
+				status?: number;
+			};
+		};
+
+		const errorDetails = getErrorMessage( apiError );
+
 		yield controls.dispatch(
 			'core/notices',
 			'createErrorNotice',
-			sprintf(
-				// translators: %s Order id
-				__(
-					'There has been an error capturing the payment for order #%s. Please try again later.',
-					'woocommerce-payments'
-				),
-				orderId
-			)
+			`${ baseErrorMessage } ${ errorDetails }`
 		);
 	} finally {
 		yield controls.dispatch(
@@ -184,6 +241,7 @@ export function* submitCaptureAuthorization(
 			'getAuthorization',
 			[ paymentIntentId ]
 		);
+
 		yield controls.dispatch(
 			STORE_NAME,
 			'setIsRequestingAuthorization',
@@ -278,17 +336,29 @@ export function* submitCancelAuthorization(
 			)
 		);
 	} catch ( error ) {
+		const baseErrorMessage = sprintf(
+			// translators: %s Order id
+			__(
+				'There has been an error canceling the payment for order #%s.',
+				'woocommerce-payments'
+			),
+			orderId
+		);
+
+		const apiError = error as {
+			code?: string;
+			message?: string;
+			data?: {
+				status?: number;
+			};
+		};
+
+		const errorDetails = getErrorMessage( apiError );
+
 		yield controls.dispatch(
 			'core/notices',
 			'createErrorNotice',
-			sprintf(
-				// translators: %s Order id
-				__(
-					'There has been an error canceling the payment for order #%s. Please try again later.',
-					'woocommerce-payments'
-				),
-				orderId
-			)
+			`${ baseErrorMessage } ${ errorDetails }`
 		);
 	} finally {
 		yield controls.dispatch(
diff --git a/client/data/authorizations/test/actions.test.ts b/client/data/authorizations/test/actions.test.ts
index 1c73ab5d7a2..171ef6dd5ad 100644
--- a/client/data/authorizations/test/actions.test.ts
+++ b/client/data/authorizations/test/actions.test.ts
@@ -16,6 +16,7 @@ import {
 	updateAuthorization,
 } from '../actions';
 import authorizationsFixture from './authorizations.fixture.json';
+import { STORE_NAME } from 'wcpay/data/constants';
 
 describe( 'Authorizations actions', () => {
 	describe( 'submitCaptureAuthorization', () => {
@@ -153,10 +154,117 @@ describe( 'Authorizations actions', () => {
 				controls.dispatch(
 					'core/notices',
 					'createErrorNotice',
-					'There has been an error capturing the payment for order #42. Please try again later.'
+					'There has been an error capturing the payment for order #42. Unable to process the payment. Please try again later.'
 				)
 			);
 		} );
+
+		describe( 'error handling', () => {
+			it( 'should create error notice with API error message', () => {
+				const generator = submitCaptureAuthorization( 'pi_123', 123 );
+
+				// Mock the start of the capture process
+				expect( generator.next().value ).toEqual(
+					controls.dispatch(
+						STORE_NAME,
+						'startResolution',
+						'getAuthorization',
+						[ 'pi_123' ]
+					)
+				);
+
+				expect( generator.next().value ).toEqual(
+					controls.dispatch(
+						STORE_NAME,
+						'setIsRequestingAuthorization',
+						true
+					)
+				);
+
+				// Mock API error response
+				const apiError = {
+					code: 'wcpay_refunded_order_uncapturable',
+					message:
+						'Payment cannot be captured for partially or fully refunded orders.',
+					data: { status: 400 },
+				};
+
+				// Simulate API error
+				expect( generator.throw( apiError ).value ).toEqual(
+					controls.dispatch(
+						'core/notices',
+						'createErrorNotice',
+						'There has been an error capturing the payment for order #123. Payment cannot be processed for partially or fully refunded orders.'
+					)
+				);
+
+				// Verify cleanup in finally block
+				expect( generator.next().value ).toEqual(
+					controls.dispatch(
+						STORE_NAME,
+						'finishResolution',
+						'getAuthorization',
+						[ 'pi_123' ]
+					)
+				);
+
+				expect( generator.next().value ).toEqual(
+					controls.dispatch(
+						STORE_NAME,
+						'setIsRequestingAuthorization',
+						false
+					)
+				);
+			} );
+
+			it( 'should create error notice with fallback message when API error has no message', () => {
+				const generator = submitCaptureAuthorization( 'pi_123', 123 );
+
+				// Skip initial dispatch calls
+				generator.next();
+				generator.next();
+
+				// Mock API error without message
+				const apiError = {
+					code: 'unknown_error',
+					data: { status: 500 },
+				};
+
+				expect( generator.throw( apiError ).value ).toEqual(
+					controls.dispatch(
+						'core/notices',
+						'createErrorNotice',
+						'There has been an error capturing the payment for order #123. Unable to process the payment. Please try again later.'
+					)
+				);
+			} );
+
+			it( 'should show default error notice for unknown error code', () => {
+				const generator = submitCaptureAuthorization(
+					'pi_unknown',
+					999
+				);
+
+				// Start the generator to the point where it would throw an error
+				generator.next();
+				generator.next();
+
+				// Mock an API error with an unknown error code
+				const apiError = {
+					code: 'unknown_error_code',
+					data: { status: 500 },
+				};
+
+				// Expect the default error message to be dispatched
+				expect( generator.throw( apiError ).value ).toEqual(
+					controls.dispatch(
+						'core/notices',
+						'createErrorNotice',
+						'There has been an error capturing the payment for order #999. Unable to process the payment. Please try again later.'
+					)
+				);
+			} );
+		} );
 	} );
 
 	describe( 'submitCancelAuthorization', () => {
@@ -294,9 +402,56 @@ describe( 'Authorizations actions', () => {
 				controls.dispatch(
 					'core/notices',
 					'createErrorNotice',
-					'There has been an error canceling the payment for order #42. Please try again later.'
+					'There has been an error canceling the payment for order #42. Unable to process the payment. Please try again later.'
 				)
 			);
 		} );
+
+		describe( 'error handling', () => {
+			it( 'should create error notice with API error message', () => {
+				const generator = submitCancelAuthorization( 'pi_123', 123 );
+
+				// Skip initial dispatch calls
+				generator.next();
+				generator.next();
+
+				// Mock API error response
+				const apiError = {
+					code: 'wcpay_payment_uncapturable',
+					message: 'The payment cannot be canceled at this time.',
+					data: { status: 400 },
+				};
+
+				expect( generator.throw( apiError ).value ).toEqual(
+					controls.dispatch(
+						'core/notices',
+						'createErrorNotice',
+						'There has been an error canceling the payment for order #123. This payment cannot be processed in its current state.'
+					)
+				);
+			} );
+
+			it( 'should create error notice with fallback message when API error has no message', () => {
+				const generator = submitCancelAuthorization( 'pi_123', 123 );
+
+				// Skip initial dispatch calls
+				generator.next();
+				generator.next();
+
+				// Mock API error without message
+				const apiError = {
+					code: 'unknown_error',
+					data: { status: 500 },
+				};
+
+				expect( generator.throw( apiError ).value ).toEqual(
+					controls.dispatch(
+						'core/notices',
+						'createErrorNotice',
+						'There has been an error canceling the payment for order #123. Unable to process the payment. Please try again later.'
+					)
+				);
+			} );
+		} );
 	} );
 } );
diff --git a/client/tokenized-express-checkout/index.js b/client/tokenized-express-checkout/index.js
index eca8a2f8a36..3b2eb1a8b46 100644
--- a/client/tokenized-express-checkout/index.js
+++ b/client/tokenized-express-checkout/index.js
@@ -326,6 +326,21 @@ jQuery( ( $ ) => {
 				'wcpay.express-checkout.update-button-data',
 				'automattic/wcpay/express-checkout',
 				async () => {
+					// if the product cannot be added to cart (because of missing variation selection, etc),
+					// don't try to add it to the cart to get new data - the call will likely fail.
+					if (
+						getExpressCheckoutData( 'button_context' ) === 'product'
+					) {
+						const addToCartButton = $(
+							'.single_add_to_cart_button'
+						);
+
+						// First check if product can be added to cart.
+						if ( addToCartButton.is( '.disabled' ) ) {
+							return;
+						}
+					}
+
 					try {
 						expressCheckoutButtonUi.blockButton();
 
@@ -375,7 +390,7 @@ jQuery( ( $ ) => {
 
 						expressCheckoutButtonUi.unblockButton();
 					} catch ( e ) {
-						expressCheckoutButtonUi.hide();
+						expressCheckoutButtonUi.hideContainer();
 					}
 				}
 			);
diff --git a/client/tokenized-express-checkout/transformers/wc-to-stripe.js b/client/tokenized-express-checkout/transformers/wc-to-stripe.js
index 867a389006b..6d9b39035ce 100644
--- a/client/tokenized-express-checkout/transformers/wc-to-stripe.js
+++ b/client/tokenized-express-checkout/transformers/wc-to-stripe.js
@@ -40,8 +40,8 @@ export const transformPrice = ( price, priceObject ) => {
 export const transformCartDataForDisplayItems = ( cartData ) => {
 	const displayItems = cartData.items.map( ( item ) => ( {
 		amount: transformPrice(
-			parseInt( item.prices.price, 10 ),
-			item.prices
+			parseInt( item.totals?.line_subtotal || item.prices.price, 10 ),
+			item.totals || item.prices
 		),
 		name: [
 			item.name,
@@ -96,7 +96,7 @@ export const transformCartDataForDisplayItems = ( cartData ) => {
  * @return {{id: string, label: string, amount: integer, deliveryEstimate: string}} `shippingRates` for Stripe.
  */
 export const transformCartDataForShippingRates = ( cartData ) =>
-	cartData.shipping_rates?.[ 0 ].shipping_rates
+	cartData.shipping_rates?.[ 0 ]?.shipping_rates
 		.sort( ( rateA, rateB ) => {
 			if ( rateA.selected === rateB.selected ) {
 				return 0; // Keep relative order if both have the same value for 'selected'
diff --git a/includes/class-wc-payment-gateway-wcpay.php b/includes/class-wc-payment-gateway-wcpay.php
index 3e02aa6acf5..4f579caf2b1 100644
--- a/includes/class-wc-payment-gateway-wcpay.php
+++ b/includes/class-wc-payment-gateway-wcpay.php
@@ -321,8 +321,7 @@ public function __construct(
 		];
 
 		if ( 'card' !== $this->stripe_id ) {
-			$this->id           = self::GATEWAY_ID . '_' . $this->stripe_id;
-			$this->method_title = "WooPayments ($this->title)";
+			$this->id = self::GATEWAY_ID . '_' . $this->stripe_id;
 		}
 
 		// Capabilities have different keys than the payment method ID's,
@@ -366,7 +365,8 @@ public function __construct(
 	 * @return string
 	 */
 	public function get_title() {
-		$this->title = $this->payment_method->get_title();
+		$this->title        = $this->payment_method->get_title();
+		$this->method_title = "WooPayments ($this->title)";
 		return parent::get_title();
 	}