Still waiting for refund GRPZARR4BMH5

On the 22 Feb 2015 I purchased a groupon voucher for R775, which was cancelled due to the supplier being fully booked when the deal only closed end of March 2015. The first available appointment was only in April. I send numerous emails to request for a refund, where our bank details were requested as we made payment via EFT. The details were provided, however the account number given was incorrectly typed and is an invalid account number. Not realizing immediately that an incorrect account number was provided on my side, I waited for the refund, as they said 3-5 working days, but nothing to date. I went back and checked my emails and realized the mistake, which I then informed Groupon that I am still waiting for my refund and that the account number they supposedly said they credited was invalid. Then I have emails from Nureen Leeman saying that the credit was successfully processed on the 2 March and 4 March ???? How can there be 2 processing dates and where did the money go to ? Surely the payment should have rejected or returned to the Groupon account due to invalid account number. I want this matter to be investigated and to be refunded ASAP.