MTN offers no help when ***** is committed on your account

Someone who went by the name of 'Wade Nathaniel' has committed ***** on my MTN account by phoning my mom stating they are from MTN security and there is abnormal activity on the account and that she must give the OTP number that is sent through. I have advised my mom countless times not to give information to anyone, however, this time they caught her out by having made it a sense of urgency.

Further to the issue above, I do not live in the country and I pay for the phone for my mom to use and when I tried to escalate this to MTN, they kept saying I need to dial 083 135 - this number doesn't work when you outside the country. After having conferenced with someone in South Africa to dial the number I got through to the call centre, but they couldn't help with the situation in reporting this and advised to email *** because, apparently *** doesn't help because they auto respond stating you need to call 083 135. MTN has offered no help in rectifying this situation and what angers me is that it is a lengthy process for me to request my invoice to pay it every month, however it was so easy for someone to gain access to my account when I explicitly said nothing is allowed to change on my account without receiving my go ahead via email.

Cannot believe how unhelpful MTN is, it is shameful!!!!