so I recently traveled to South Korea from the us and my phone has been acting weird since I got here. first I got a notification saying "activation incomplete your phone will try again when you restart" then I noticed my apps would close or "refresh" after a short time of having them open. Facebook will refresh every 10-15 seconds. apps, like games, will close randomly every 20-60 seconds. never had this issue before getting here. I've factory reset the phone twice now. didn't change anything. tried running clean master. restarting the phone multiple times. deleting anything to free up space. nothing helped. not until I removed my sim card. which for some reason completely fixes my phone. it goes back to acting normal. besides the fact that now I can't text/call. anybody have any ideas on how to fix this issue without having to get a new sim card? not many Verizon stores around here 
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