vovotelo steenberg villiage do not honour their specials advertised

A sign outside this store offering from Monday to Friday between 3pm and 5pm a flat white + slice of cake for R49. The bill Inv. No 4105 at 3.36 I was charged the full amount of R46 slice of cake & R26 flat white. I left , but returned immediately after seeing the special board outside the door. When I enquired the waitress Felicia said it is only after 3pm ? we sat down at 3.10 and then placed the order. Eventually the bill was rectified, no apology from either manager or waitress only the waitress asking how much does she needs to refund me back . It is quite obvious they really take a chance & hope the client wont notice, this is certainly no way to run a successful business. I blame management for failing to educate the staff as to specials etc.