I just picked up a used verizon G2 to use on the Straight Talk service. First issue. I pulled the sim card from my old straight talk phone and put it in the G2. It instantly said unknown sim but, when i restarted the phone i had service. Problem is, i still have the unknown sim icon and cant seem to use LTE. Second issue. im stuck on 4.4.2 because it will not allow me to download any system updates. Im hoping there is a way to manually update. Any help would be greatly appreciated!