Restraining order.

I have a restraining order on my ex husband. He is currently incarcerated, but he still continues to call me, sometimes 20 times a day. One day, it was about 30. Sometimes, it’s only 5. I have never been to jail and don’t the ins and outs. How is it even possible he is able to call so many times in one day?

I won’t be changing my number. It’s a more complex situation. I’m not really concerned with the phone calls, I’m just wondering how this is even possible “behind bars”, and if there’s a restraining order in place, he should know he shouldn’t be calling. Oh, in addition, I want to have easily accessible proof, in case it needs to be presented in court.

I do have proof it’s him because it’s the same number that’s connected to the department, and the voicemail always says “You have a call, at no expense to you, from “he says his name”, to expect this call press 5”, and so on and so on.

Thank all of y’all for your responses!! They’re very much appreciated!!