Exkash.com Stole 1600usd in bitcoin transaction Internet

 Simple ,safe, exchange bitcoin for cash directly into bank account. Thats what Excash promised so i sent my 1600usd worth of bitcoins to the address they provided. I then received an email stating the transaction was not complete. They had not recieved the bitcoins. But my wallet is empty and the transaction record show s that they indeed did receive the bitcoins. That was on 7/5/2017.and now 2 weeks later ive had no correspondence from eckash.and no money tranfered too my account . And bitmain tells mr theres not a d**n thing they or anyone can do too retrive my funds . What a joke ,a very expensive joke.