Fujitsu aircon not cooling, but also not showing any error message. Fujitsu charges 10,000 only to look at it. Any idea what could be?

Since this is a domestic model, I think the post is suitable for Japanlife. Searching in English I only got info about stuff related to the large central units used in the US and searching in Japanese I didn’t find any info about this specific issue.

Model: Fujitsu AS-J22D-W

Problem: Aircon was working fine but then stopped cooling the next after. No error is shown. It still turns on and seems to “work” for hours without giving any error but also without cooling.

* It’s not a gas leak, as gas leaks give errors (also the gas has a red coloring to help identify leaks and I didn’t find any around the piping).
* The fan on the external unit doesn’t spin and the radiator does not get hot.

I’m totally lost as to what is the problem. Since it was a cheap aircon, fixing will certainly end more expensive than getting a new one, so I’d like to troubleshoot it myself before just throwing it away. Any suggestions about where to start or what to try?

This aircon has had a gas leak before that was fixed by Fujitsu authorized service (during warranty) and at some point it probably had some water ingress that gave me shocks when touching the external unity when wet (lol, that’s what you get for buying the absolute cheapest aircon).