Our old robot vacuum was in household room and somehow it got a bit wet and it went unnoticed. Water creeped up the dock via capillary action. PSU board got hevily damaged.

So my solution was to throw damaged PSU (230VAC > DC 20V 1.8A) out and replace it with USB Type-C power board I had laying around.

Hotglued the USB power board on the original PSU-board. Sometimes things just work out - holes lined up, original PSU was 20V that USB PD can deliver etc!

Total time: opened dock on shelf after diagnosis - months. Actual fix after realising the solution - about 30 minutes.