Placed on contract I did not sign for

On the 22nd/23rd Feb I walked into a Vodacom Store to get the Special for the iPhone5 on a Flexi 150 for R200 that I signed for. I paid an admin fee and was told R300 will come off my account in 48 hours pro rata. After a week of waiting for approval (the stores are unable to do this due to a system migration) I am told I was approved and everything is up and running. <br> I check my bundle and seem to have R200 airtime when I know I should only get R100. When I call Vodacom Call Centre, I am told I have been placed on a Flexi 200 for nearly R400 a month. <br> I called the store who confirmed, that I indeed signed for a Flexi 150. They immediately attempted to contact Vodacom to cancel and resubmit the package. It is now the 30th or March and nothing has been fixed. The Vodacom Store has provided me with written proof that they have been trying to contact Vodacom to rectify yet nothing has been done!!! I will now be charged double what I was meant to pay and was told I am not allowed to reverse the payment as my credit will be affected!!! <br> So in essence, Vodacom is *****ing from me and in breach of contract!!!!