HD8854 05 error due to defective brewing unit

After replacing the 3-way valve, the machine worked again. Then cleaned the brewunit thoroughly.
Then an 05 error. Device starts up. After restarting gives a humming sound and the message "Filling system"
You can see the water in the reservoir sinking. However all the water ends up in the coffee opvcang tray.
It seems that the inlet of the brewunit is not positioned on the nail behind the brewunit and therefore all the water ends up in the coffee collection tray.
Anyone idea on this could be the cause of the 05 error and does anyone have a repair tip?
Manually putting the brewunit in "brewing" position is sometimes very difficult due to the position of the shear plate on top of the unit.
Any tips?