Sign into your MyVerizon account online as the account owner. Navigate to the Block Services section and block the Visual Voicemail feature and block the Premium Visual Voicemail feature. This will set you back on the basic voicemail. You will have to set it up again though.
This however contingent on you not having an iPhone. If you have an iPhone, the only voicemail option you have is a visual voicemail system.
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.