Please help me.
I sent ETC to GNT wallet. Can I get it back?
I sent it from Yobit to Upbit. By the way,
Yobit has not responded for 4 months.
Upbit says it’s impossible.
Sent Time: 2018-03-28 11:03:05
Volume: 13.07478724 ETC
TXID: 0xa2857b9b848bb907035561ca93dfb30b6cd6c72601d5fbf6f0343defb3e06b4b
If they say it’s not possible they can’t do it. If you do not got any control of the wallet you also can do nothing. I feel sorry for you. The next time duble check everything and never send from a exchange to another exchange.
Later if ETC go to the moon, I’ll try one more time to get it back.
Thank you.
As @MM_MarioMichel pointed out, it is completely up to the exchanges to oblige to help or not. Unfortunately you don’t retain the same control on exchanges as you would with a desktop wallet like Emerald or Daedalus. Sorry your having this issue. 
I think if I have the private key I can get it back.
But the exchange said they could not help me.
Perhaps they don’t want to give me the private key.
And they want some fee to recovery it.
Sadly, Now, the fee they want is bigger than 13 ETC.
So I think there is a possibility someday.
When ETC go to the moon.