Give us more info,from where you send USDT and what service/wallet you use for BCH?If you have private key for that BCH address the problem should be solved relatively easily by creating account here : https://www.omniwallet.org/ and then import BCH private key to get access to USDT.

If you send USDT to some exchange then you need to contact their support and hope they can help you.

this is where wallet developers/coin creators need to stop copy and pasting code..

if coin developers just used an address that did not start with a 1. they could easily do an error check that tells users, 'seems you inputted a non-usdt address'

what do you mean "nothing on both sides"? Did you check the delivery address under USDT block explorer and it is not there?

Also, do you own the BCH address (read: do you have the private key to that BCH address)? Chances are, but I am not 100% sure as it involves both USDT and BCH, but chances are you can use THE SAME private key to access the delivery USDT address, too.

So here is the instructions:
1. check the delivery address on USDT block explorer, and
2. if the funds are there all right, you can try to get your funds back by
  2a. instaling USDT wallet and
  2b. sweeping that address with your BCH private key.

Don't confuse USDT and BCH from my post (again), though, because you will only make matters worse Good luck!

Then it will be lost forever! That's the danger of being in a platform where there is no regulation at all and decentralized. You will never be able to know where you sent it and if it really has a valid address. So better be careful when you transact with crypto currencies especially during initial coin offering. Double check the address first, or better yet just copy it.

i sent it from my exchange polonex to another exchange and i contact the support, no replay from more than 10 days

i sent it from one exchange to another, i submit support ticket but no replay

Depends on where you sent it. If you can somehow get the private key for the addresses then there might be a chance you could get your money back, but otherwise then there's no chance of your money back. Hopefully it wasn't that much money man, I'm sorry

I think its not possible to recover your coins But you contact there support centre .They can help if delay to responce i think you lost your coin .

If you sent out that USDT to a good exchange, then i am sure that in the next month, or maybe more than months you will be able to recover that money.
But now, if you sent them to Coinbase, Bittrex, HitBTC or Binance, consider it as lost money, since they are never going to reply you back.

I do not know that either it can be recover or not, but i do not think  that there is any mechanism to recover your money that you lost by mistakes, onece the transaction is done it cannot be reverse, therefore it is too much important to be much more carefore while sending bitcoin or any other altcoin through exchange as we cannot recover the fund that you will lose even by mistakes.