Who I have the same questioned this topic

I ordered a replacement iPhone 6 on Thursday and I received it on Friday. I got it set up and it was working perfectly fine when I added it to my number, I then made it the primary phone and and the connection to Verizon no longer stayed. At first I just restarted it, and it would work then the phone would freeze. So, I took out the SIM card and put it back in, that worked. The phone will have a network at school and home but it will then switch to searching or no Service, and i made sure the bill was payed and nothing happened. Please help I have to return my old phone soon, and I don't want to be without a phone.