False adverti*****t or **** ****

I'm totally disappointed with rage. seriously this isn't on . they sent me a birthday voucher today as it is my birthday today, now I went to de store to redeem it they told me it's already be redeemed in September but I explained my birthday it's today and I'm here today to redeem it they insist I've already redeemed it how because I only have one birthday. even now I'm puzzled I don't understand how can I redeem birthday voucher in September while my birthday it's in December and their voucher expires in 7 days even wasted airtime calling support centre but still get the same result I'm very annoyed and angry 😡 they must not promise customers what they can not give or fullfil....... For me it's false adverti*****t