Billed for two months again on cellphone contract

I took out a contract with Telkom Mobile two months ago. It was in the first week of the month, so I was given the option to have it debited the first month or to have both the first and second month debited at the end of the second month. This amounted to R311 which included the activation fee etc. which was debited from my account at the beginning of June 2015. <br> <br> The contract is roughly R120 p/m. But this morning they debited another R311 from my account. The contract that I signed is not R311 p/m. This is unacceptable. <br> <br>