Mystery voucher nr does not exist

I received a SMS on 21/03/2015 to Say Hello Winner. Take this Mystery TFG voucher no F6D8E7AD0B24929 to any Foschini or TFG store before 31March its worth between R10 and R10000.00<br> On Sunday 29/03/2015 i went to Foschini Clearwater to purchased two blouses and obviously wanted to redeem the voucher nr that was send to me via Phone. The Sales lady had to issue me with a new Foschini card as my card was outdated. I waited about 10minutes for that eposide to finishas she struggled to get through to Customer Services . The when she entered the voucher nr the system just says it does not EXIST. Then she phoned customer service again battling to get through again and I wait another 15minutes without any luck. THey just put her through from the one person to the other. I waited more than 25minutes and then told her just leave it. Why sending me a sms with a voucher number if it does not even exist. I am very dissapointed and felt that I have lost out on what could have been a discount towards my purchases