How do I fix the Apple ID verification on my phone?

I'm going to try to be as specific as possible. So I've had this phone for a good year, Year and a half, and the entire time I haven't had this problem. I had always been signed into my Apple ID. But today, it had a pop up that said I needed to verify my email. If I clicked not now, it would pop right back up. When I clicked go to settings, it would ask me to enter my password and after I did so, it would pop up asking for my password again. i know it was the correct password because when I used a different one, it popped up saying incorrect password. I did multiple resets and after the fourth one, it seemed to fix itself. I took a nap and when I woke up not only was it back to doing the loop, it wasn't allowing me to join the wifi. Please help