Flipkart — About account block.

My Flipkart account has been blocked by Flipkart. They cited unusual number of return as a reason for blocking account. I was unaware of any such policy. Atleast they must warn me about policy. However I contacted Flipkart and apologise for fault done unknowingly by me. I repeated requested them to unblock my account. How they can block my account without any warning. First they should tell me about the policy. If I have committed mistake there must a way to solve the problem but they are doing nothing.