Call customer service at 1-800-922-0204 from another phone and request the representative reset your voicemail from their end and walk you through the steps to set it up.
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.
allyraz316, let's make sure we can get your voicemail up and running as soon as possible. Did this start after a recent software update? Have we attempted to Reset Network Settings on your device?
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If my response answered your question please click the _Correct Answer_ button under my response. This ensures others can benefit from our conversation. Thanks in advance for your help with this!!