I have two s21 ultra phones which I purchased directly from Samsung. I told them I am a Verizon customer. Three times now, on each phone, in different locations the phone refuses to make a call and displays the message “you are not registered on any network.” I took the phone to a Verizon dealer and we reset the network settings, made sure the phone was not roaming, and restarted the phone. All good for a couple of days when the same thing occurred. This time I restarted the phone and that seemed to resolve the problem. The third time, I took it to a Verizon dealer and we replaced the SIM card. All settings are correctly set. This is an annoying problem for such an expensive phone. Come on Samsung. I know this phone has a great camera but it is, after all, a phone and what good is it if it keeps refusing to let me make a call?
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