diff --git a/.github/workflows/opensearch-observability-test-and-build-workflow.yml b/.github/workflows/opensearch-observability-test-and-build-workflow.yml
index 606303f39..c62ff163b 100644
--- a/.github/workflows/opensearch-observability-test-and-build-workflow.yml
+++ b/.github/workflows/opensearch-observability-test-and-build-workflow.yml
@@ -58,7 +58,7 @@ jobs:
           cp -r ./build/distributions/*.zip opensearch-observability-builds/
 
       - name: Upload Artifacts
-        uses: actions/upload-artifact@v1
+        uses: actions/upload-artifact@v4
         with:
           name: opensearch-observability-ubuntu-latest
           path: opensearch-observability-builds
@@ -90,7 +90,7 @@ jobs:
           cp -r ./build/distributions/*.zip opensearch-observability-builds/
 
       - name: Upload Artifacts
-        uses: actions/upload-artifact@v1
+        uses: actions/upload-artifact@v4
         with:
           name: opensearch-observability-${{ matrix.os }}
           path: opensearch-observability-builds
diff --git a/build.gradle b/build.gradle
index ea3a3166c..480bbda76 100644
--- a/build.gradle
+++ b/build.gradle
@@ -21,7 +21,7 @@ buildscript {
             opensearch_build += "-SNAPSHOT"
         }
         common_utils_version = System.getProperty("common_utils.version", opensearch_build)
-        kotlin_version = System.getProperty("kotlin.version", "1.8.21")
+        kotlin_version = System.getProperty("kotlin.version", "1.9.20")
     }
 
     repositories {
@@ -124,6 +124,7 @@ configurations.all {
     resolutionStrategy {
         force "org.jetbrains.kotlin:kotlin-stdlib:${kotlin_version}"
         force "org.jetbrains.kotlin:kotlin-stdlib-jdk8:${kotlin_version}"
+        force "org.jetbrains.kotlin:kotlin-stdlib-jdk7:${kotlin_version}"
         force "org.jetbrains.kotlin:kotlin-reflect:${kotlin_version}"
         force "org.jetbrains.kotlin:kotlin-stdlib-common:${kotlin_version}"
         force "com.fasterxml.jackson.dataformat:jackson-dataformat-cbor:${versions.jackson}"
@@ -149,11 +150,11 @@ ext {
 }
 
 plugins.withId('java') {
-    sourceCompatibility = targetCompatibility = "11"
+    sourceCompatibility = targetCompatibility = "21"
 }
 
 plugins.withId('org.jetbrains.kotlin.jvm') {
-    compileKotlin.kotlinOptions.jvmTarget = compileTestKotlin.kotlinOptions.jvmTarget = "11"
+    compileKotlin.kotlinOptions.jvmTarget = compileTestKotlin.kotlinOptions.jvmTarget = "21"
 }
 
 allprojects {
@@ -161,7 +162,7 @@ allprojects {
 
     version = "${opensearch_build}"
     plugins.withId('java') {
-        sourceCompatibility = targetCompatibility = "11"
+        sourceCompatibility = targetCompatibility = "21"
     }
 }
 
diff --git a/src/main/kotlin/org/opensearch/observability/index/ObservabilityIndex.kt b/src/main/kotlin/org/opensearch/observability/index/ObservabilityIndex.kt
index 7a8f0dfea..a61ecbd11 100644
--- a/src/main/kotlin/org/opensearch/observability/index/ObservabilityIndex.kt
+++ b/src/main/kotlin/org/opensearch/observability/index/ObservabilityIndex.kt
@@ -104,10 +104,10 @@ internal object ObservabilityIndex {
                     error("$LOG_PREFIX:Index $INDEX_NAME creation not Acknowledged")
                 }
             } catch (exception: ResourceAlreadyExistsException) {
-                log.warn("message: ${exception.message}")
+                log.warn("skipping creation as resource already exists: ${exception.message}")
             } catch (exception: Exception) {
                 if (exception.cause !is ResourceAlreadyExistsException) {
-                    throw exception
+                    log.error("index creation failed due to exception: ${exception.message}")
                 }
             }
             this.mappingsUpdated = true
@@ -169,11 +169,10 @@ internal object ObservabilityIndex {
                         "and ${reindexResponse.updated} docs updated in $INDEX_NAME"
                 )
             } catch (exception: ResourceNotFoundException) {
-                log.warn("message: ${exception.message}")
+                log.warn("skipping reindex notebook as resource not found, message : ${exception.message}")
             } catch (exception: Exception) {
-                if (exception.cause !is ResourceNotFoundException) {
-                    throw exception
-                }
+                log.error("reindex notebook failed due to exception: ${exception.message}")
+                throw exception
             }
         }
     }