ᐅ Kospel Amicus, small point-of-use water heater in the kitchen is leaking

Hello everyone,

For a few days now, unfortunately, our Kospel Amicus tankless water heater under the kitchen sink has been leaking. It has been in use for several years without any problems until now.
The leak is quite severe, filling about half a cleaning bucket per day. It seems to be dripping regardless of whether water is being drawn from the tap or not.

I am not familiar with this device. Maybe someone can tell me from the pictures whether the problem can still be fixed or if I should dispose of it.
So far, I have only found leaks around this round component with screws. It appears that the water is coming out around the screws.

I appreciate any help.
Best regards,
Matze