Bad customer experience

I ordered a size 1 sneaker online when my order came through I received 2 different sneaker sizes.(a size 1 and size 13) I Went to the Cresta branch to exchange it however no size available the gentleman told me if I wanted it immediately I must drive to one of the other stores to exchange it to which I objected, why should I be driving around to correct a mistake of the service provider. I was then told that they will order it from a neighbouring branch as I told them I will not be driving to another branch for a mistakes that’s not mine. The consultant told me it will take 3 days to arrive on the 2nd April I still got no feedback I called and then was told 5 days still feedback I went into the store on the 10th April to be told the sneaker has still not arrived. I am now so fed up of sportscene they show no interest in rectifying there mistake in no positive way but rather keep telling me I need to wait.