Honestly, there isn't anything you can do in this case. The problem here is that the player is designed for and locked to a specific region while you're attempting to play a disc from another region. These region codes were set up by the movie studios to help prevent piracy, and there is no easy way around them. While you may see some “hacks” online, they are not applicable to all models, as most do not have the ability to be overridden by a software adjustment, including yours.
This region coding protocol is physically built into the hardware (chips on the control board) of the player, and changing it would require physical modifications to the player (swapping out chips) that would void the warranty and often permanently damage the player.
Your best options are to re-purchase the discs you want to play in your country with the proper region code, or buy a purpose made region-free player that does not have this hardware restriction.
I'm sorry there isn't a more optimistic answer here, it's simply a design limitation of the player.
Best regards, ***** ***** for the answer,