Customer service "Groundhog Day" with unresolved problem

aside from taking her back down to a physical store you can try contacting them through one of their social media platforms like Facebook or Twitter..this lands you with tier 2 support instead of the tier 1 call in agents.

also if you havent already you might have your mom put you as another allowed person on her account to make changes..that way youre on both and can make the changes for her without having to include her...since you dont have a line on her account im not sure if they can assign you as the primary account holder of hers account...maybe?