I can’t set up a voicemail password

I am trying to set up my voicemail. I try to set up a new passcode and I get a voicemail error message every time. It Started with my new iPhone plan I set up earlier this year, I just let it go and went without a voicemail till my phone broke and I had to get a replacement through AppleCare. I tried to set a voicemail up on this one and I get the same error message. Please help!