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11 Invalid SIM message when I try and put SIM card in?
I have a 7 plus I bought for a customer, but when I put their Sprint SIM card in, Sprint shows in the top left corner for a second, but then it goes to invalid SIM. What could be the cause of this issue? I’m almost certain that this is a Sprint phone, but will check later today. For now, assuming that is not the issue, what else could be the matter? Thanks for the help!
