Phone is automatically adding a + to my numbers.

I switched providers from Verizon to Pure Talk. My phone that I have is a Samsung S7 edge. Everything works fine, except all my incoming calls end up with a plus in front of the number. I can't return the call because it thinks it is an international number. Any solution on how to resolve the issue? I know the carriers are different, so it is set the phone for GSM. I think Pure Talk thinks the solution is to buy a new phone. I am not sure if Verizon has locked something in the phone to prevent using it on another carrier. Any help would be appreciated.

Welcome to Android Central! Open your Phone app, go to its settings, and look for an option for Assisted Dialing. Make sure that's turned off, and see if the problem goes away.

And if it doesn't, talk to Pure Talk again. They're causing the problem, so they have to fix it. (Even though it's going to be very expensive for them. They have to redesign a decent portion of their system.)

(Pure Talk uses AT&T, and AT&T doesn't do that.)