What is this error?
This is a version code mismatch error in the google play android developer console, this can be fixed by increasing your app's version code to a greater number.
To fix this error, open Android Studio and load the app files. you have to generate a new signed APK with a different version code, here is how we can do it:
Right click on project window, and select Open module settings
Go to flavors tab
Increase version code and name, and then generate new APK. this should fix the error
That's it, now just sync the project and create a new signed apk, try to upload it to the console .