Number Share on Razer Phone 2 on Verizon (US)

Hello, I recently got a smart watch that is 4G compatible and when I went to the Verizon store to setup number share all the other lines on my account were available except for mine (owner of the Razer Phone 2). Is there anything I need to do to get it to work. Has anyone else been able to get number share to work? Any help would be greatly appreciated. -Jaycub