The toilet float valve I use is of the brand Geberit.
It keeps leeking water because it does not close anymore.
I guess the metal pin at the front needs to move when the green elements move up.
Does anyone have some ideas what I can do to make it work? I tried pushing and pulling it gently, but it looks very fragile so I don't think it's a good idea.
I've also put it in vinegar for a night, without any success.