Are you saying that nothing happened then you knocked? Sadly, the game seems to have all sorts of bugs, but usually you can walk back a bit and then try pressing E again.
Unfortunately there's so sound feedback for the knocking, but if you check out the playthrough files I've shared into the server, you'll see I tried every distance, and for quite some time! Thanks for letting me know that's it's really just a bug though - will you be working more on this?
