Cant edit my T-mobile Voicemail on my Verizon Galaxy S4

[AC Question]

So im looking to change my voicemail. I have a Verizon Galaxy S4 mini, with T-mobile carrier. When i click on the voicemail app, it says "Unable to verify subscription status. Please try again later." And when i go to the phone dial and hold down 1 to access my voicemail it says "Call can not be completed as dialed, please check fhe number and dial again." I can dial my own number to listen to my voicemails, but i am unable to change what my voicemail says when i get a missed call. Looking for quick answers! Thanks in advance!