PlatformException: Invalid package name

I am able to fetch and display the packages. The purchase seems to work on the play store because if i try subscribe to the same package again it says its already in use. The problem is that the purchase is not syncing to the sandbox. I get the following error below:

PlatformException(23, There is an issue with your configuration. Check the underlying error for more details., {code: 23, message: There is an issue with your configuration. Check the underlying error for more details., readableErrorCode: ConfigurationError, readable_error_code: ConfigurationError, underlyingErrorMessage: Invalid package name., userCancelled: false}, null)

I have the app in the internal testers track on the play store, i am running my app in debug mode. The version on the playstore reads: 3 (1.0.0) and my app version reads: 1.0.0+3. 

I am very confused as to what i am doing wrong