I have an Android APK in the Google Play store with an Target SDK of 23.
I have released a new version (same target SDK) and Google shows me this error:
If I
I got able to resolve this issue:-
The issue was with the versioncode - I am sure you have not defined any version code in your App and it is getting generated by this formula:
versionCode = MAJOR * 10000 + MINOR * 100 + PATCH
But sometimes auto generated versioncode value of the latest release becomes smaller than the previous release (in your case 10403 < 104028) and that's why it shows non-upgradable APK.
What you need to do is:-
In your config.xml in tag add versioncode like below:-
android-versionCode="104280"
104280 will work for you as it is greater than older version.
Now get it published without any error.
Thanks Sanny