Sportsbet.com, sportsbet.org, sportsbet.it, sportsbet.whatever are all wrong. If someone already used the platform for so long, and new register users whom actually sent their money to new register accounts, they should remember the site address: sportsbet.io. Later, whenever they want to visit the site, typing the address is what they must do.
Some people use so many platforms, and they don't remember site addresses, so they search through Google, that in turn sometimes will show links of phising sites.
sportsbet.io
However, at the same time the name is basically the same, it is sportsbet.io versus .one and that is a trick. I am thinking maybe they are not trying to do phishing but they want to make sure they get the name in there so that they can use the marketing you have done so far to make sure people mistake it with them and actually legit play there, so its not stealing peoples money but its stealing your marketing.
I mean it could be absolutely nothing to do with you as well but we can't be certainly sure until they do something about it.