You can change the default ringtone for all incoming phone calls from your Android's settings app:
Tap on Settings >> Dialer & Calls >> Touch sound & feedback >> select phone ringtone >> select a ringtone.
You can change the default ringtone for all incoming phone calls from your Android's settings app:
Tap on Settings >> Dialer & Calls >> Touch sound & feedback >> select phone ringtone >> select a ringtone.