Each line on the account can have their own My Verizon account for contact management, purchasing ring tones, and ringback tone purchasing and management.
You will need to sign into the My Verizon account associated with your line and not the account owner's My Verizon account. You will have to buy the ringback tone again under your line.
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.
