Getting CredentialsError: Missing credentials in config, if using AWS_CONFIG_FILE, set AWS_SDK_LOAD_CONFIG=1 while ECS task tried to publish message to SQS

[yashaswinib-ds]

We are getting error while ECS service is trying to perform below actions

When attempting to publish a message to SQS
When trying to store an object in S3
When attempting to publish to SNS
We have verified that the AWS credentials are correctly configured in the environment.
The AWS SDK is being used, and we have set the environment variable AWS_SDK_LOAD_CONFIG=1 & 2.
This issue is intermittent, as our service retries to publish the same message until the next attempt is successful.
Other microservices using similar configurations are functioning without issues.
Despite our attempts to resolve the problem, we have not been successful. We reached out to the AWS IAM support team - and cleared out the issue isn't on roles and permission used.

I as wondering if this is a SDK version issue. But I couldn't raise the SDK support ticket in AWS as there was no option.
Can anyone please give me some guidance here?
Will the SDK upgrade provide us the solution for this? Or should I look in any other direction?

P.S Thank you