Xiaomi India — mi a1 after oreo update

My phone hang in 4gb ram it is working like of 2gb smartphone please send me an update which solves this. The front camera is like of 2 mp there is no clearity in this mi a1. The key board is also hanging too much at this time and sometimes phone does not work i have to restart my phone this is the worst phone i have ever seen in price of 15000 rs the note 4 back camera is pretty good but this dual camera is not so much impressing only portrait mode is good. After updating in oreo there is lots of hanging problem in my mi a1