Somehow I installed SMS voice message notification that would send me a text message that I had a voice mail. It told me to call 650-603-0000 but when I called that number all I got was a busy signal. I could not figure out how to disable sms so went to the Sprint store and spoke with the manager who had not idea what was going on so he went into settings - applications - voicemail. He asked me if there were any messages that I needed to save and when I told him no he then p[ressed clear data and then fpressed Force stop AND IT WORKED.
Now I get my voice mail messages the normal way. Thank you Ryan.........
If you do have messages you need to save you can also try to just reactivate your visual voicemail from your phone. Go to the Voicemail App. Click the compose message button in the upper right corner (looks like a microphone with a + sign). Record a message for a few seconds (doesn't matter if you say canything, it can be blank). Press the share button in the lower right corner. Send using the Voicemail app to firstname.lastname@example.org. IT may take up to 15 minutes to reactivate and provision your account on the phone.
Note these instructions may be slightly different for different VVM capable phones. I used my Galaxy S3 to get the step by step instructions.