I\'ve just now started using app bundles. I\'ve set the two certificates in the App signing section of the dashboard (signing certificate and upload certificate
The solution was a very basic one. I had to clean my project and then rebuild it.
Android Studio was signing my app bundle with the old certificate i was using.
What I did previously is go to Build -> Generate Signed Bundle / APK and i changed the jks file in the file selector to the new upload jks. It seems Android Studio caches the old certificate path and uses it even though I've selected a new one. Might be a bug in AS.
So yeah ... now if I clean the project every time i change the jks file it works, the apk or app bundle gets signed with the proper certificate...