App ID change causes APK uploading error

Hi,

We are about to upload a new version of AppLab App to support IAP, and here is our problem:

1. The previous version APK for production channel actually used a wrong App ID
2.In order to support IAP, I switched to the correct App ID, however when I'm trying to upload the new version APK, I always got an error message:
"ERROR: Please sign or rebuild your APK using a production certificate or verify your keystore build settings are correct."

Any suggestions to solve the problem?

Thanks a lot