Can not add a user or email

My wife is still using her AOL email from 1999.  I tried to add her as a user on our xfinity account a few months ago so she can have a comcast email.  When I did,  it wouldn't work and kept looping back to an error message.  I gave up.  She is having more issues with AOL blocking and trashing emails before she sees them.   Now when I try to add her on xfinity it says there is already a user with her phone number.   But she is not listed as a user.   

Thanks!