Samsung - Samsung warranty claim denied

I bought Samsung f** Mobile on June month fm Flipkart... On **th of aug suddenly screen got flickering and total screen become black out... immediately I called customer care and they gave me service centre contact no in Chennai chrompet .... I called them but no response and directly went but no response and ask me to come on **th aug..they checked my mobile but not infront of me...they claimed this doesn't come under warranty since water log issue been found...I asked them for proof they simply showed the dust particles near charging area and said this is fungus...I am not satisfied with their reply because Its new Mobile I not used in any water conditions...they denied to show me further proof of any circuit damage or any other reason...I just need to know whether I got a defective piece fm Samsung or their model is such a cheap worthy product can't withstand simple condition also.. service centre people r so rude to me and they r in process of denying warranty claim...I need replacement or warranty claim or refund for my repair....plz take immediate action reg this...