Refund issue

I booked 2 tickets to Capetown on the 19th May to fly from OR Tambo to Capetown 23 June and back 25th June to OR Tambo. All tickets were paid but on my surprise 23th June on my way to Capetown i received an email that my 25th return ticket has been cancelled.To my surprise i tried to phone travelstart but i didnt get any positive answer instead they told me the flight has been rescheduled for a late time. After that telephonic call i received an email that i should provide them with my last ten numbers for my card for refund which i did immediately. Mind you now my vacation is spoiled with no return ticket. After i sent the numbers they told me its going to take 3 to 7 days for the refund. I had to borrow money to return back and from 23 June until today 07 July no refunds from this nonsense agent.Ive been writing emails and busy telling me 3 to 7 days but now its the 7th July from 23 June. I will never use travelstart again