Original post by: maidmarr ,
I got a new LG Rebel in August 2016 to replace my Samsung Centura. (well I think that's what it was). It was a 3g phone. I travel back and fourth to Canada and NEVER had an issue with the old phone for over a year. The new one starts to read Invalid Sim Card as soon as I cross the border and nothing will fix it, right to tried a full factory reset. Got a new sim card from Tracfone, it worked for 3 weeks, went to Canada again and before even getting across the border I guess i picked up a Canada Cell tower and the 4g LTE LG Rebel started showing Invalid Sim Card message again. Stayed in spite of all that was done by me, tracfone tech etc, until I put in a new sim card. It has worked for well over a month since then and now I'm back in Canada. I shut the phone off before crossing the border and removed the battery so hopefully when i go back to the states it starts up and works no problem. But seems if i cross to Canada or hit a Canadian cell tower it starts to flash the message and nothing but a new activated sim card makes it work again.