Good morning, moner256. I apologize for any confusion. You do not need to be the account manager if you are listed as the account owner. Please visit this link (https://secure.verizon.com/account/roleInfo/start) to see all the things that you can do as an account owner and the things that an account manager can do.
Why would you want to be listed as an account manager if your name is already listed as an account manager? Are you not able to do a specific thing with your account or service?
Please share specific details, we want you to have an excellent experience and we can help.