SIM card not working with Honor 5x
So I had a Samsung Galaxy 4 as my last phone and it was getting kinda glitchy and bad so I decided to switch to the Honor 5x. When I went to the AT&T store in my area the worker tried switching the Sim card and it wouldn't work. He then brought out a new sim card and messed around with my settings to finally get it to work (it took an entire hour). However, soon after getting home my screen said "No service". I personally have tried taking the Sim card out and cleaning it. That worked for an entire day until it just randomly stopped working? Is it a problem with the Sim card itself, the phone, or software? Has anyone else had this problem?