HI,
Google Play Store only accepts AABs on new apps
(if you previously uploaded an APK for this app you may still be able to)
The DS official/technical team probably need to know the version of DS, the version of the builder (these two should match),
and perhaps the version of Android. The exact message from Play Store may clarify the cause.
Have you uploaded any apps before? Have you uploaded an APK for this app before?
If you have uploaded before then you need to build with the same keystore.
Regards, ah