False radio advertising

Went to get the R19.95 birthday Big Mac medium meal special advertised on radio stations and Facebook only to be asked where my coupon was that I was meant to have collected in the morning. No mention was made of collecting coupons and limited to first 500 customers. Poor staff attitude and false radio advert has assisted my decision to NEVER purchase another item from any McDonald restaurant in South Africa again! Well done in celebrating 20 years with angry customers!!!!