msamsung j5 is stuck on a ringtone and saying default unknown wont let me change it saying setting unavailable
Hmm.. Try using Ringdroid (link). Download a custom ringtone and use it with Ringdroid. Let me know if it works.
Happens the same to me. I think it is because the phone is overloaded with data and cannot recognize them, because it didn't hsve that problem before. Don't really know.The only waý i could find was restoring the default settings. but there must be a easier way.