Poor service at Dobsonville Standard bank

My mom who's a pensioner banks with you. She forgets her pin so I tried installing your app on her phone. To my surprise, the phone number on her account doesn't belong to her. She went to the bank to have it updated and was told it was done but it wasn't.

Since I was at work and couldn't accompany her, I asked my niece to go with her but she was declined entry at the Dobsonville Standard bank. So who's number is on her account? Why wasn't her number updated? Her phone uses her print so if locked, no one else can use it. Why did the banker refuse installing the app for her?

Please update her phone number and explain whose number is that on her account and who added it there.