********* price changing

Visited the OR tambo branch , wanted to buy a shoe on special. The size that they showed me was a size 7 the price was on special @R1279.00 . I am a size 6. They told me they have a size 6.5 so I said I'll take it . When it's time to pay they said the size 6.5 is not on special yet it's the same shoe , this is very upsetting . Please sort this matter out