home key not working'

The DZ09 is a Chinese smart watch with basic features and calling ability. These can be as cheap as $10! (Yes, you read that correctly!)So is it worth look into it?will you be able to find part replacement if required?usually i don't deal with this kind of repairs if the end result will be the same.it doesn't matter if you are capable of doing the repair or not,the question still remains if it's worth it.....and that being said you have tried all the basic stuff as reset,restart,ect......