Ok. .I had this problem for over a month on both of my phones. I just fixed the problem. Call yourself from his phone. Hang it right up. It will pop up a screen . There will be a green M in the left corner . Go to settings button on it . Click it. On the bottom you will see the writing that says black list. Click it. Take your number off. Then you will see white list. I personally clicked it , and put my numbers in to never block again. If you have any problems. Inbox me.
I had a similar problem if you have a phone clearn like speed cleaner or anything some have callblocker on them check there thats what happened to me i put my friend number on there some how
Its an app called super security. Its an M with a symbol around it. Unblock your number, and remove the app