Not receiving my voucher from Unipin

I transferred R100 into unipin account as I previously have done and no voucher was sent to me dispite emails and sms's and again there is no number to contact to follow up. Im so frustrated and not sure how this business is run if they do not respond. Very annoyed...I have previously complained about this and still no change. Im still waiting from yesterday for the voucher to be sent and still nothing.