Incorrect exchange rejection reason

I purchased many Crocs online from Crocs SA. I am Very disappointed in my last shipment. I opened the box and the enclosed plastic, fitted on the Crocs and immediately realized it's too heavy to walk on it. I then placed it back into the plastic together with the other croc that still had its tag on and I closed the plastic and put it back into the original box. I took pics of the croc as per the return policy. And requested a refund. The courier collected the next day. I received a mail from Shana Leigh today to advise that the reason for me not receiving a refund is that it is over worn.! This is totally incorrect. I am shocked that this is the reason. I want this to be thoroughly investigated and the original pics to be reviewed when I sent it with the courier. Very disappointed with the reason by Shana Leigh