If your AWS CLI configuration is missing or corrupted or set in multiple locations with a miss match, then you get this error. To fix this error first determine how you have set your AWS CLI credentials. If the credential is set in a file (~/.aws/credentials) then check the content of the file and if required reset it again with aws configure command as shown below
## Check current credentails
If you are using environment variables to set AWS credentials then check if AWS_ACCESS_KEY_ID environment variable is set properly and reset if required.