S10 randomly rings.

Welcome to Android Central! Is it your default ringtone, a notification tone, or something you've never heard before? Does it go away if you turn off NFC?
 
Also as a test, turn off NFC and see if the problem persists. If it does, then try installing Nice Catch from the Galaxy Store and see if that can tell you if an app is trying to give you a notification.
 

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