Johto Region Access

Hello, I'm having some trouble getting to the Johto region. I have tried going through the Pokémon League, but every time I go through the door that would lead me to Route 26, the game plays montage of stills from the credits scenes of pokemon movies before transporting me back to pallet town. I cannot work out how I'm supposed to get to the Johto region.
Can anyone help me with this, please?

This game is still under development, and players can't go to johto region yet, the credits mark the limit of the Demo.

I'm the creator of this big project and i worked all alone for 5 years or more, so the game isn't finished yet.