I just checked the casino out and every thing seems cool, i dont know which country you base but I visited the site from my Nigerian ip address and it's cool, no such pop up or what so ever.

If you have been using or playing on this casino before now  without any of such problem, and today, this issue pops up, there is no better way to explain this than say they it's possible the casino have added your region or country to their blacklist, and I think the best thing you can do right now is contact their customer care for a more better and clear explanation of what really is happening..

So lets not assume things for its possible this could as well be as a result of error in their system or something of that sort.