Fix java.lang.IllegalStateException: 'You need to use a Theme.AppCompat theme (or descendant) with this activity' for specific devices

Question

I get this in crashlytics. I understand we could use AppCompat versions for theme. But why I'm getting this crash only for a certain device? As of now, only one user, Having Android 9 Vivo phones.

Caused by java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.