Unacceptable service from MTN

Good morning

I write to you regarding the unacceptable service that i have received from MTN. On the 16 October i called MTN to upgrade my contract with them and forwarded the documents they requested, On the 25 November MTN deducted R1118.00 which we never agreed on , when i query about it they told me that the contract was cancelled by one of their employees . I further apply for an upgrade [***], forwarded all the document's they requested they never responded. The service i have received was unacceptable and they have an attitude when you ask relevant question.

Regards, Nhlanhla