I don't know if it's still the same, but a few years ago I needed my phone to ring longer. I called customer service (800-922-0204) and they adjusted it for me. Mine now rings either six or eight times.
It is set at the system level at 30 seconds. It can't be changed. Sometimes a different ringtone helps.
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.