Cheat and ***** on free stay

On the 4 October i received a sms at 14:02 with regards to a free stay at one of their destinations...i immediately phoned sun international to make a booking (within 5min of receving the sms) and i was told they are fully booked for sun city. Now please tell me how is it possible that within 5 min of receving the sms the whole of sun city is fully booked until next year. This is not the first time this has happened to me everytime i receive a sms with a free stay its the same story......I MUST SAY SUN INTERNATIONAL SERVICE IS PATHETIC...........THEY LIE AND SEND YOU FALSE SMS FOR FREE STAYS SO YOU CAN CONTINUE PLAYING AT THEIR CASINOS WITH NO BENEFITS