I have a problem similar to this question, but it is not identical.
When I build the AAB file and upload it to Google, I am given the error
The following APKs or App Bundles are available to 64-bit devices, but they only have 32-bit native code: 6.
When I build the game I can see the progress window saying it is building the 64 bit source. So why does Google keep telling me it doesn't contain a 64 bit version?
From unity forum:
x86 is used by less than 0.4% of all Android devices, so it shouldn't have any real impact.
You may probably already noticed but in 2019.2 x86 target is marked as deprecated, in 2019.3 it will be removed completely.
Deselect x86 architecture in Player Settings.