invalid vouchers

i recently won vouchers on the Vodacom Unlock your Summer competition and it was R200 voucher and my niece as well won the same price. So when i tried to redeem the voucher they were invalid so i called and was advised that there was an error but they are working on it . i received an email advising the error has been fixed i can redeem the vouchers i have been trying for more than 2 wees now and im using desk top to log in the netflorist website and i have sen messages more than 6 times and im always getting the same answer i requested for a call back but still nothing .

im so disappointed