Nokia India — Problem in back button

Address:

Mumbai City, Maharashtra

As i got update on my Nokia lumia 830, & after updating my mobile software in version 8.10.14234.375, my handset Back key touch is not working properly, even sometimes window touch key is also not works, for working these both key i have to first touch anywhere on screen and then im able to use that back touch key . . i dont know whts problem it with these newer version, but as i was using my handset in old version i didnt get any problem in that older version, the problem which im facing in these old version . . plz guide me for these, what should i do . .? or update your software version and send we lumia user for updating our software again with no issues . . and evn many things are there, like no proper inbuild apps for videos or movie sharing to other mobiles, evn cnt hide personal images or videos, NO OTG support in lumia 830, no option is there for select all images or videos single singel we have to select which is very disgusting, not all video format is suporting hardly few formats suports, plz do some changes in newer version of your OS, even no seperate folder get create if we take images through bluetooth or through NFC, battery drains fast . . and many things are there . . . but these are the few things which i want to say . . and the main imp is the problem which im facing after upgrading OS in newer version . .