How to pass string value to initiateOnDeviceConversionMeasurementWithHashedPhoneNumber?

[jerinjohnk]

initiateOnDeviceConversionMeasurementWithHashedPhoneNumber function takes a string value as input.
For example

const hashWordArray = SHA256('+15555551234');  // hash Array
const base64Hash = hashWordArray.toString(Base64);
initiateOnDeviceConversionMeasurementWithHashedPhoneNumber(
    analytics,
    base64Hash,
  );

Now whenever I try either toString() or a Base64 encoded string, as soon as

NSData *phoneNumber = [hashedPhoneNumber dataUsingEncoding:NSUTF8StringEncoding];

Breakpoint hit; the byte length is around 44.

[FIRAnalytics initiateOnDeviceConversionMeasurementWithHashedPhoneNumber:phoneNumber];

After nextline's execution, it starts throwing error
12.4.0 - [FirebaseAnalytics][I-ACS025057] Hashed phone number should be 32 bytes (256 bits)

Till creation of hasWordArray is fine according to the documentation, but I am at a loss for how to convert this to the expected string format acceptable by the library.

Firebase Version

"@react-native-firebase/app": "23.4.1",
"@react-native-firebase/crashlytics": "23.4.1",
"@react-native-firebase/database": "23.4.1",
"@react-native-firebase/in-app-messaging": "23.4.1",
"@react-native-firebase/messaging": "23.4.1",
"@react-native-firebase/remote-config": "23.4.1",