Non Actioning of Migration Instruction

After being billed almost R20000 over two months for data charges, I decided to migrate to a top up package, which would restrict Internet access when the 3Gb limit was reached. I requested the forms which .I completed and emailed back. Vodacom failed to honour my written request. Months later I sent a complaint in this regard. A person named Lauren responDed requesting proof of submission. I immediately furnished same. It's going 7 weeks and the has been no response whatsoever. This is a clear reflection as to what went wrong due to the inefficiency and incompetence on their side. Vodacom has to refund me all data charges they ********ly charged me since date of receipt of my written instruction to migrate the package.