AwsIamAuthentication fails with Credential should be scoped to a valid region when migrating from spring-vault-core 2.3.3 to 3.1.1

I have upgrade from spring-vault-core 2.3.3 to 3.1.1 and using AwsIamAuthentication

public ClientAuthentication createClientAuthentication() {
AwsCredentialsProvider credentialsProvider = DefaultCredentialsProvider.create();
AwsIamAuthenticationOptions options = AwsIamAuthenticationOptions.builder()
.credentialsProvider(credentialsProvider)
.region(Region.US_WEST_2). I have tried adding this filed in 3.1.1 as vault and instances are in us-west-2
.role(InfrastructureInfo.getInstance().getVaultRole())
.build();
return new AwsIamAuthentication(options, VaultUtils.getRestOptions());
}
Exception-
org.springframework.vault.authentication.VaultLoginException: Cannot login using AWS-IAM: error making upstream request: received error code 403 from STS: ](https://sts.amazonaws.com/doc/2011-06-15/%22%3E)

Sender
SignatureDoesNotMatch
Credential should be scoped to a valid region.

b38c3d6a-ae0a-4f08-b768-94ad7b53b82e

Java-17
SpringBoot-3.2.0
Spring Framework- 6.1.+

From CLI I am able to read data.
Vault v1.9.4

Start with AwsIamAuthentication and the createClientAuthentication configuration shown in the report, reproducing the migration on Java 17, Spring Boot 3.2.0, and Vault 1.9.4. Compare the AWS IAM request and region handling between spring-vault-core 2.3.3 and 3.1.1, then verify the fix by confirming that login succeeds against the us-west-2 setup without the STS region error.