ECAM 22.36 70% of water ends up in the drip tray

Hello friends,

stand before a problem with our KVA, the ECAM 22.36
.Since a few days lands only extremely little to no coffee in the cup, in 50-70% of cases, the cup even remains completely empty.
The error is somewhere before or at the black container which is shown on 2 of the following 4 pictures, the 2 other pictures show the outlet of this container which leads to the collection container.
Unfortunately being clueless about engineering I don't know where to start, there are 4 to 5 or even more hoses connected to said tank.
All I can say is that the water "bends" the wrong way at a point I don't know and then ends up in the catch tank without coming into contact with the ground beans.

Maybe someone has a tip for me, I've gone through reports of other machines with the same problem, but that always looks very different from mine...
the water what mistakenly ends up in the drip tray is clear and the warranty has expired virtually perfect
....