I have seen many situation as you before OP and those experiences were from known exchanges a few years ago. Lucky those people that have been helped by the team to receive the wrongly sent bitcoins to omni layer/protocol.
But this time, it's hard to reach and make the exchange do the favor to you and might just say that it's your fault.
Hi, thank you for your reply. May I ask you why you think that exchange now may say me it's my foult ?. May you explain this a little bit? Is it about of Poloniex company or about of me ? Thanks..
Because you haven't checked where you're sending. I haven't used Poloniex for a long time but when you're about to deposit, is there any warning or message that to check the address where you're sending before you make a transaction?
In the past, that's what I've read when somebody have the same experience as you, he'd explained a lot and his mistake and then the exchange told him that they can no longer retrieve the wrongly sent coins back to him.