I am seeing Indonesia, and AFAIK they don't exactly have a good relationship with online gambling. I've seen indonesian players changing their DNS settings to bypass blocks by their ISP as these blocks are typically at a domain-level only.
Exactly.
One of the affected members said he was from Indonesia and that’s why I said the restriction might most likely be from the ISP and not from the casino. Besides, when it’s the ISP is the one blocking access to a certain website then you will, most of the times, see the "404 not found" pzge, while you will only see "you are not allowed to acces.." or something like that when the restriction is from the webstés side.