how to rectify this error "InvalidIdentityPoolConfigurationException"

Hi - Please check If you have added the Identity Pool to IAM Trust Relationships.

Sure, here are the steps to check and configure the trust relationships for the IAM roles associated with your Amazon Cognito Identity Pool:

1. Log in to the AWS Management Console, and navigate to the IAM service.

2. In the IAM dashboard, click on "Roles"

3. Look for the roles that are associated with your Amazon Cognito Identity Pool. These roles are mostly named based on your identity pool name with "Cognito_" as a prefix.

4. Select the role for either authenticated or unauthenticated users (whichever is relevant to your use case), and click on the "Trust relationships" tab.

5. Click on the "Edit trust relationship" button to modify the trust relationship policy.

6. The trust relationship policy defines who is allowed to assume this role. Ensure that it contains a condition allowing Amazon Cognito to assume this role. The condition should include the Cognito identity pool's identity provider as the trusted entity.

Note : IAM roles and policies are critical for granting permissions within your AWS environment. Make sure to review the policies and trust relationships carefully to ensure they align with your security and access requirements.

Reference : https://aws.amazon.com/blogs/security/how-to-use-trust-policies-with-iam-roles/