Hello @Jjtyork and Welcome to the Samsung Community Forum 👋
Try a forced reboot by holding down the volume down key and power button simultaneously for more than 7 seconds to restart it. When your phone resets, you will feel it vibrate.
As a process of elimination can you try your sim card in another phone to see if your sim card works fine.
And if possible another sim card in your phone.
The phone does have a Diagnostic Tool 🔧 found in your Samsung Members App to see if that highlights anything.
In your Settings you can also reset your Network.
Settings > General Management > Reset > Reset Mobile Network Settings > Turn your phone Off and On.
If you perform a forum search you may find existing threads with some further help or guidence within.
If the troubleshooting steps do not help and your sim works OK in another phone then a Samsung Service Centre can help > https://www.samsung.com/uk/support/repair/
If i can be of any further help please don't hesitate to ask 😎
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. "
