Some custom notifications keep resetting

[Vighpyr]

So this has been a problem for a while now. I have several of my contacts configured with custom notification sounds. Some of them work fine with no problem. Others always reset to default after one or two messages. Is there something I'm missing? 

I basically just edit the contact, and specify the specific sound I want for SMS notifications for that contact. Works once or twice, but then resets. Any ideas? TIA!

[Midge123]

Hi there I have the s20 ultra and I have noticed if I have some updates it puts some of my contacts to default it used to annoy me but now I know I just check every time updates comes along hope that helps a little thanks