Voicemail Error Try Again Later

This advice is definitely helpful. Prior to receiving this email, I did contact my service provider and was told to dial "1" or the phone's own number. The phone's number worked but not the "1". This gave me an audio menu that allowed me to set up the voicemail. Having input a numerical password at the promptings and disconnected from the menu, I then went back to the voicemail screen on the phone app and entered that password there. That completed the set up and voicemail was working. I'm not sure if this same procedure would work with other service providers, but you could give it a try if you've stumbled onto this thread.