My deposit refund

I served my two months notice and vacated the premises on the 30th of September, I was told that I have to wait for 6 to 9 weeks before I get my deposit refund, I waited patiently for 9 weeks. I called them after that 9 weeks & I still did not get my refund, everytime I go there or when I call their offices I get a new story but as a tenant if you pay your rent late, you will get all sorts of threats: from threatening emails to smses how they gonna cut off your electricity if you don't pay in time.