Not that weird if you ask me because I experienced it in few different casinos but with different game providers.
I do not know what cause this or the reason behind this thing but high possibility there is a change in the terms of the providers itself or about the deal between the casino and the providers.
I do say about the deal/agreement because I experience with providers which restrict my location in few casinos but it does not in other casinos or vice versa.
As always, asking the support of the casino may give you the best answer related to this case.
Restrictions on a casino would go in hierrachy as follows.
Casino restriction first, then game provider restriction in a flow of restriction. For example, if a casino restrict one nation, even a game provider does not restrict users from that nation, those people will not be able to register and use an account on that casino. If a casino does not restrict one nation, it means people from that nation generally can use all products and games on that casino with exemptions with restrictions from game providers.