My Nexus 5 all of sudden can't register to cellular network. So I tested my sim card to friends phone and it works as it should. I tested his sim card to my Nexus 5 and it works! I am all confused, I even did a factory reset to my phone. I even wasted money on a new sim card too. Still does work. Koodo kiosk I went to didn't even have a demo or sample phone to test sim card, poor service. Any help would be appreciated before I go on spend money on a new phone.