Cartrack taking their time to refund me...

Hello Peter, I would like to get assistance with Cartrack as the last 3 years I have been debited twice for my car, and on. January I called them to rectify their mistake and I wanted my money back that was debited for the past 36 months. On march they called to me confirm the corrected their mistake, and said they will deposit my refund in 7 to 14 days and I am still waiting for them 40+ days later. It's tiring calling them to remind them it's actually 40+ days later and nothing is done their side. Please assist