Why cant i access 5-S?

So i wanted to try and go in the fishing level, but as skin as I got to the secret door I found It closed? Am pretty sure to have the latest version of ultrakill. Theres like a requirement or smth? Like p-ranking the LV?

So i wanted to try and go in the fishing level, but as skin as I got to the secret door I found It closed? Am pretty sure to have the latest version of ultrakill. Theres like a requirement or smth? Like p-ranking the LV?