Fantasykicksa they sold me fong kong

Fantasakicksa i saw it on Instagram it is an online store that sells sports wear...I have purchased a pair of sneakers...but they did not send me the ones that they have advised they have send me something else. They dont want to refund me ...when i ask them to exchange they refuse also can you plz help me to get my money back or exchange. The guy who was helping me is Thabang Maphanga his cell number is ***