So, my SIM on the phone keeps getting blocked or freezing. This happened three times already. Before anyone says anything, yes, I paid the bill (more details below) 4 months ago I woke up one morning and the SIM was not registered on the network, nothing worked. Going into safe mode didn't work. Doing a factory reset didn't work. What solved the issue is getting a new SIM. About 3 weeks ago, this happened again! So, I did a little playing around. I even got a 2nd phone, exactly the same model. The SIM itself was locked as if I had entered the PIN wrong, but I didn't. The phone was completely accessible, other SIMs worked in the phone. I could not import/export contacts. When I changed the SIM at the carrier, it fixed this again. But, they told me they'd have to take my phone. Today, this happened again! Same issues. I am tired of going to my carrier and having to prove to them that I paid my bill and this issue is theirs and it is ridiculous to have them take my phone since I need it for business. Any ideas on what the issue is?