I've read already about phishing sites where the OP logs immediately after you (if the timing is right, I assume), so the 2FA is still good.
And it's enough to send the money to another account of the hacker (since for withdraw another 2FA is needed and the hacker cannot be THAT fast).
The good thing is that afaik Bitsler team use to be careful with the withdrawals, so the hacker has a very good chance he cannot withdraw your money, especially if you report that quick enough.
Basically some phishing attempts these days are pretty advanced. If you got an old copy of windows without any updates. It can mess with your DNS and redirect to the phishing sites IP address.
Hence you should never surf those warez or porn sites which got like 20 ads opening up. Because some of them might be some java script to mess with your DNS.
Only way to protect yourself is if you notice something strange like a failed login when it shouldn't be failed and if for some reason they ask for the 2fa twice almost immediately .
For all these issues you should use the best antivirus then even though if you visit some phishing sites it will block all those viruses. Never go for pirated version because you may not get updates so you still risking your PC. So I'm using premium version Norton antivirus software.
Always check the site URL clearly before entering your user id and password.
The virus software usually doesn't help you. These are usually 0day exploits.
There was someone who somehow got some weird virus and even in the correct domain name it was forwarded to some other DNS.
Basically the cache was cleared from his browser and so it looked like his HTTPS was new and the browser didn't suspect anything suspicious.
Hence you need to pay attention if you are getting wrong passwords when you shouldn't or if it asks you for 2fa twice instead of once.