Misleading advertising

I have had an account with Edgars from the 1970's and never defaulted any month in all this time on paying my account by the end of each month. Towards the end of April 2020 I received an SMS (one of multiple) that if I pay my account at any Checkers Store I would receive a R 25 gift voucher. My account was duly paid before the end of April (as I always do in any case), however up to now no such gift voucher was received. Although a small amount this blatant misleading of the public is unacceptable.