Crocs SA unfair treatment

I have had some good experiences with Crocs SA over the past few years. Recently I've contacted them to exchange my defect shoe. Unfortunately it's over month now that I've contacted them 3 times via email and ones by telephone. They seem to be of no help and i have received absolutely no response from them. I am very disappointed. Has anyone else also revived this kind of treatment ? I will not support them until they resolve my situation.