A second issue that pops up all too often is if the old phone has a lock of some kind. This can be the old "locked phone" to an IMEI lock where the phone was subsidized and the owner has not finished paying on the plan. These locks are well known but there's always someone that will try to get their 99 dollar iPhone over on another carrier and the block can not be removed. Long discussions why this is.
Can I bring my own phone and use it on Verizon network? The issue is the type of phone is GSM from T-Mobile it's LTE. I was hoping to just put a Verizon SIM Card in and go from there but I don't think I will be able to am I right?

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