Android marshmallow released for infinix hot 2

just recently I updated it to marshmallow, and there are some improvement, especially that of security, download and enjoy, but you know in every new development there's always a bug and some of the bugs in the marshmallow update for infinix hot 2 are..
it's lags: it's something takes up to 3 to 5 secs for the phone to wake up when the screen is off and takes a few sec to respond to your touches.
one other of the major bugs I've found is that once upgrading,all your files on your internal storage lost, so I strongly Advise that before you upgrade  it you should backup all your datas and files on your SD card.   after upgrading your internal storage show that it's been used but you can't assess what's using the storage and I thank the remedy for it is to factory reset. and also battery drains, if you experience battery drain you should always the software to settle for a few days. thank you these are the problems I've found for now.