You are correct that some members have reported similar issues to yours.
As well as moving the sim to the secondary sim slot you could also try these troubleshooting steps @Mark TKO
https://www.samsung.com/uk/support/mobile-devices/my-galaxy-smartphone-has-frozen-how-do-i-restart-i...
Settings > General Management > Reset > Reset Network Connections > Reboot the phone by turning the phone Off and On.
Clear Cache Files from the phone's System Partition Section > https://www.samsung.com/uk/support/mobile-devices/how-do-i-clear-the-cache-on-my-device/ You may need to insert your earphones or hook upto a powered On Laptop or use a Tv's USB Port to access the Clear Partition Section. This may help with lag or stutters as this clears the phone of old/unused or broken cache files.There is also a Repair Apps option in the Menu System too { Possibly excluding the s²⁴ Series of phone's }
As a process of elimination can you try your sim card in another phone and then if possible try another Sim card in your phone.
There is a diagnostic test tool found in your Samsung Members App.
Feedback can be sent from your Samsung Members App too.
Please let us know how you get on.
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. "
