You'll have to call customer service at 1-800-922-0204 to request they add the Block Voicemail feature to your line.
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.
We want your account and service to be customized to your needs, and we are here to make that happen. As previously mentioned, we will need to access your account to block voicemail. I have sent you a Private Message so we may continue. Thanks in advance.
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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!!