Relaxo Footwear — Boston/ crack on surface

Address:

Lakha bhajar gabhana aligarh

I were bought boston shoes in september from relaxo showroom railway road aligarh. He gave me 6 month warranty of any kind of damage. I rarely use my shoes only 1 month now its surface get cracked. According to this present condition i can't wear it any more.
So please tell me the process to replace my item as soon as possible.