Didn't you say "it worked after changing the location"?. I thought you were getting some kind of error, as you said, and after changing the location, it worked fine. However, I just tried a VPN and I can confirm that the website is now loading faster and there are no problems. So, it proves that it is not my internet connection. It is from the hosting provider of the casino.

I am not sure if the problem could be from my ISP. My ISP should not slow down any the internet for any specific website. They block the website directly if they get instructions from the government. A lot of websites are blocked already that I cannot access without a VPN.