Can you try a soft reboot by turning the phone Off and On.
Also ejecting the sim card and gently wipe the chip on the sim with a soft cloth and re insert can help.
If all else fails back up and factory reset @Terasa
If you Google Search > Samsung phone shows as emergency calls only < there are quite a few help pages and there are some existing threads on the forum.
The usual issue is the phone not connecting to a cell mast @Terasa
If I can be of any further help then please don't hesitate. Take care. 😎
Daily Driver > Samsung Galaxy s²⁴ 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. "
