Dear Sir I had purchase one K4 note from Amazon 10th Feb 2016 vide invoice no KA-BLR6-144105041-8896729, I like to inform you that the following problems are arise within this time. 1) within one month sim not detected your Authorized Balasore service center M/S S.S.Infotech replaced mother board & kept the phone more than 10 days in their service center 2) again after 2 months external SD card not detected & again they replaced mother board keeping the phone more than 15 days 3) on 17/10 2016 no display problem arise replaced mother board the problem not solved . within eight month of warranty period my phone was laying more than one month in service center. You may contact your Authorized service center for detail clarification. In this situation I am requesting you to replace my phone set immediately other wise I will go to consumer court.

Regards
majichittaranjan@gmail.