I opened up an account with Sportsbet.io and deposited about 250 dollars worth of bitcoin, after I had won my bet I tried to withdraw and it did not let me. Eventually the team wanted me to KYC which I did successfully. After a couple of days, they replied that I had used a double spent on my bitcoin and took my winnings and my deposit. I tried emailing them again because this was 100 percent not true but they have not been responding to me. The day I deposited my bitcoin there was a backlog on the blockchain. Eventually I sent the same transaction again so that it could be confirmed quicker. But this ended up getting my money taken. I have only heard good things about sportsbet.io and it sucks that this happened to me. Most of my friends and even my girlfriend had an account with them that works fine. Of course it?s me that got the crap end of the stick. My username is jumpy192
If it is a double spend, that is actually a problem on your end and you can't blame the service (in this case Sportsbet) for it, since they never actually received the money. They have a policy for 0 confirmations on BTC chain and it is one of the best features of the site but can get you into funny situations if you are not sure how BTC network works. You can't withdraw before your deposit tx gets confirmed as a safety measure.
I actually had similar problems not so long ago and was quite pissed with Sportsbet before I realized what actually happened. My wallet, Ledger Live, was stupid enough to create double spend when I had 2 consecutive transactions. I sent first tx and it wasn't confirmed when I sent the second one. Problem is wallet itself sent the remaining money from first tx on change address but did not update that in its own database (it gets updated only after tx confirms). Then it tried to send second tx from the initial addy instead of change addy which was obvious double spend after first tx got confirmed. I got to the bottom of it by myself trough btc chain diagnostic and live support did not help me much in the process and that is the only thing Sportsbet could have handled better. On the other hand I know it is impossible to expect from live support to know everything about the site and all the crypto chains Sportsbet supports.
Still using Sportsbet of course but Ledger Live is history and I will never use it again if I can avoid it