@Adrianna2
This could be your network provider or the sim card is failing.
As a process of elimination can you try your sim card in another phone and then see what happens.
When you unlock your phone does your phone make and take calls Ok ?
Try a soft reboot by turning the phone off and on.
A Samsung Experience Store / Samsung Service Centre can run a diagnostic too.
Daily Driver > Samsung Galaxy s²⁵ Ultra 512Gb ~ Titanium Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "
