False advertising

Do you guys really understand customers service or it's just a word. Yesterday I went to Checkers Sandton City to buy a few things costing R814 the lady gave me a receipt that said congratulations I get R80 of my next purchase coupon. The ticket is valid for the 5th and 6th of January mind you I don't have a Checkers around were I stay we only have a Shoprite. So today I went to Checkers today to use as I won't be able to use this weekend I was told I can't. The lady that said that didn't even offer a voucher for Monday atleast. She didn't care. Please stop this false advertising. You shouldn't have bothered giving this to me nxn.