Vodacom penalize me for their fault

I have evaluate every network in my area and Vodacom used to provide the strongest signal because I have direct line of sight to the Vodacom tower from my house. So I signed up for a Vodacom data contract. About the same time my router was delivered, the Vodacom tower got vandalized. I have reported the issue numerous times and Vodacom does not seem to be committed to get the tower online again. I tried to cancel my contract, but I have been charged a penalty of R1920. Why do *I* have to pay penalties if Vodacom's coverage changed because they are not committed to keep their towers online?!?