Horrible service from Vodacom

I phoned Vodacom to cancel my one contract as we didn't need it anymore. They then told me that I qualified for a free router with 5GB of data at a vey reduced price. I received the router promptly, but to this day, I stll only get the 2GB of data as per the old contract and it has been month since the "upgrade" I called on the 17th of April and received a reference number. I then received a sms stating that they closed the case, but I wasn't notified and nothing changed. I phoned again on the 9th of May and was told that they are investigating and that they would call back within 24 hours. I am still waiting. And the same thing happened to my other contract with them as well. I will be cancelling all my Vodacom contracts as soon as they expire.