Telkom has not delivered on their promise

I signed a two year cellphone contract with Telkom in January 2018 (Free Me 1 Gig) with the added benefit of 10 Gigabytes for three months.

I was not allocated this and now Telkom are dragging their heels not solving my problem.

It's been more than a month since I lodged the complaint and notification but I have had no joy from the call center. Typical response "it's still being investigated" "They will contact you". The only "contact " I received was an sms to say "your case is being investigated " whilst I'm having to buy data on a regular basis!

So rediculious as I thought their customer service improved since I last has a contract with them. Disappointed! Cannot talk to a manager! How do I cancel this contract?