Thanks all mate. I updated the conversation with Duelbits support so far in #1. They don't give me the time frame so I just wait. I will post a message in their official topic so they can get notice.
Honestly, this is my own mistake. So I must take whatever result, I can't blame them.
Technically, I think that they have private key and can retrieve the fund. But it can take a long time so they don't give me the time frame.
You are very right, it is indeed your own mistake, and I believe no body is above making mistake, even duelbits should understand this is they don't already..
And for me personally, I think what you should be talking about is for when they will be chanced to help you retrieve that funds, we understand that they are a big business and have a lot of customers to attend to on a daily, but aside this, practically, retrieve the funds shouldn't take them up to 5 minutes, most especially if they have the private key this the wallet handy, which I believe they should since it's your deposit wallet which is also a hot wallet they withdraw from when ever you make a deposit, play and loss games,
So just give them time to make out time to help with the recovery.