Instant cash issue

I am actually appalled at this standard bank instant cash option.i withdrew money from my betway account and chose the standard bank instant cash option, it was a big mistake.the next morning betway sends me an sms with the voucher number and pin.when I went to withdraw it at a standard bank ATM it said that the voucher has already been used.i queried this with betway and they advised that I need to sort it out with standard bank.i even tried to redeem the voucher at shoprite and the same that it was already used.how could someone use my my voucher when I am the only person who has access to my fone? And while I was on Facebook I realised so many people has had this issue with the instant cash thing.its really bad service for such a big bank, I will never ever use that option ever again really.with other banks u always have to punch in your mobile number as well. How on earth will I get my money back? I always thought that standard bank is a really good bank, and I figured the instant payment should be quick but an absolute nightmare