Hello and sorry if I'm posting in the wrong place!

I have an issue with my ringtone. I have assigned a custom ringtone (.mp3) for my phone (all contacts, no preferencies), but after reboot or after switching between "silent" and "general", the ringtone goes back to "Nokia Tune". If I look up in the settings->profiles section, the highlighted ringtone is the custom one, however, all I hear is Nokia Tune...

Any ideea on how to sort this out?
Thank a ton!