The terms and conditions provide the answer that @Tardif cannot register on the rollbit.com site because his country of origin is listed on the list of countries that are not allowed by rollbit.com because it conflicts with rules and policies even though the rollbit site always presents many promotions to players.
Sorry @Tardif if you come from a country that is prohibited from registering on our site.
I quoted the terms and conditions shared by @logfiles.
Let me quote for you the list of banned countries from their Terms of service
You are not allowed to register on the Website and use our services if you are a resident of Aruba, Australia, Belgium, Bonaire, Curacao, Cyprus, Denmark, Estonia, France, Germany, Hungary, Iran, Iraq, Italy, Netherlands, North Korea, Saba, Slovakia, Spain, St Maarten, Statia, Turkey, Ukraine, United Arab Emirates, U.S.A or the U.S.A dependencies, United Kingdom. We reserve the right to refuse customers from any other countries over and above the aforementioned jurisdictions at our own discretion.