Faulty Toshiba Hard Drive still under warranty

I bought a 1tb Toshiba external hard drive on the 20th of December 2013 at Incredible Connection Vaal Mall. At the beginning on of the year it started giving me problems. Then on the 2nd of March 2015, I returned it to the store, who then submitted to the supplier to have it repaired. I was told it would take under 7 working days. About a week later, Bongani called me to tell me the supplier couldn't fix it, so they will be sending a new one in another week. 2 weeks after the call I went to the store to ask for the product back. I was then informed that the supplier claims it is out of warranty. I argued that the 2 years haven't lapsed & I was told the matter would be taken to higher levels. I kept coming back & everytime I did, there was no progress. The assistant never even called me to reassure me during this period. The hard drive was very convenient for me, now it seems like I will be getting it back in the same condition I submitted it in. I need a remedy for this situation ASAP