Irregular upgrade

I have recently contacted the Vodacom regional office in Bloemfontein to enquire about an upgrade on my father's contract which he did not request. He was contacted telephonically by a representative of Vodacom informing him that he qualifies for an upgrade. He informed the lady that he would prefer to go to a Vodacom shop to do the upgrade in person. When he got to the Vodacom shop a month later to do the upgrade he was informed that his phone contract as well as his data contract was already upgraded. When he requested information about the so called upgrade he was referred to the Bloemfontein regional office as apparently they could not assist with that kind of information. We visited the Vodacom office on 08/06/2018 but were told that the only person that would be able to help us was not in. We left our contact details and to my surprise she actually phoned us back later that afternoon. She promised that she would investigate and come back to us, but never did. I phoned the number she contacted me from but nobody answered. I then visited the office again a week later but she was once again not in the office. I left my contact details but haven't heard from her since. The number I have just keeps on ringing. We cannot find out why my father's contract was upgraded despite him informing the sales consultant that he would prefer to do so at a Vodacom shop. We cannot even find out on which contract he is now. He never received confirmation of the upgrade in the mail. This is terrible service from Vodacom!