From you above message did it sounds like you bought an S7 Edge? If so how have you found it and did you buy through Taobao?
It is easily the best phone I have owned. The software and hardware are solid. My only complaint is the glass back which attracts fingerprints and grease. I ended up putting a thin Ringke slim case on it.
I bought on taobao from a seller who had already sold a few hundred other SGS 7 Edges. If you do buy from Taobao then go for the popular shops that have hundreds of thousands of phone sales. If there is an issue then send the phone back immediately. I bought an LG G3 a few years back and they sent me the wrong model, Korean instead of HK. I had no trouble returning it, but had to wait a few weeks for stock of the HK model.
Another tip is to request a receipt for the phone from an authorised Samsung reseller. I paid a little bit extra for this. Samsung will not honour the warranty in mainland China without it.