Breach of contract

Since I got my ADSL line from Telkom on contract I had very little to no service at all. I made use of their sms line, FB page, local store to no avail. I ordered my adsl line from an advert on FB posted by a person working for Telkom called Thuli ( ********** 113) He's been helpfull but can't seem to do anything on his side. After numerouscomplaints from my side they descovered that the main cable running through all the houses in my street was faulty. It took them about two months to replace. Now it's been replaced but still no adsl or wifi. I can't stop the service because it's a contract. Can I take legal action for breach of contract?