Does Travelstart normally take 2 months to refund me? Not impressed......

I cancelled my car rental booking ref MU*** on 23 March. Its almost 2 months later and I haven't received my refund yet. I am currently very frustrated. I dont understand what the delay is. All my other cancellations showed my refund back in my bank account within 2 weeks of processing. I really hope this refund will include interest seeing that it took so long. The car booking was paid for by credit card which charges 20% interest per year. I didn't settle my credit card seeing that the refund will be paid back to my credit card and I didn't expect it to be this long. I even got an email from Travelstart and Cartrawler as soon as I processed the cancellation that the refund will reflect on my account within 20 working days. Why do you guys send the mail if it doesn't happen like the mail states? Please assist to resolve this issue