Mtn do not secure accounts

My mom is an old age pensioner and some somebody *******ly made a purchase against her mtn account into to the about of 700. And you you are telling her you may need be able to reverse and you will need to wait for next invoice. Firstly she did not make the purchase so you cannot hold her liable and secondly why does she need to wait and be punished with anxiety. Reverse it now. Refund it now.