Very dissapointed in CAT footwear and Tekkie Town

We bought CAT footwear at Tekkie Town in Jacaranda Centre on the 3rd of February. I wore the shoes only once and it caused me blisters on both ankles and the left shoe pressured my foot so bad that I weren't able to wear it again.

We went to Tekkie Town today to exchange it, but the manager refuses to return it, because of the fact that they can see that it has been worn.

I was so excited about wearing my R1700 CAT footwear, but now it has caused me much more dissapointment.

Is there any way in which TEKKIE TOWN or CAT footwear can assist us?