Stuck because MTN refuse to help

I called customer care because I loaded airtime and it did not go in. My phone is a contract phone which is listed under my mother, we have two devices on the contract. We have declared to mtn insurance that I am the primary user of one of the devices but the consultant refused to help and said only my mother can call in, my mother is halfway across the country so that's not feesible. And now I am stuck without airtime that I need