Smelly AC. Professional cleaning not effective
A bit of backstory first.
3 years ago we moved into a brand new rental mansion, nobody lived there before. It has 4 new AC units with all the bells and whistles like thermal camera, remote control, self cleaning, various features etc. Kirigamine MZS-ZXV2822-W.
First summer was fine, no issues. But starting from the next summer, 2 out of 4 ACs (living room and office) started giving off musty stinky smell after some hours of operation.
Then I read online that you're supposed to run them in fan mode for 30 min after using cooling mode to dry off condensation. So I turned on a cleaning feature that kinda does that, plus it warms up the air to dry the radiator fins.
Now my room is stinky AND warm. This warm air seems to only amplify the smell and make the room super humid. I literally have condensation on cold objects.
We do clean ACs from dust and wash removable parts twice a year. Plus it has dust collecting mechanism that runs automatically.
Last year we tried anti mold spray - didn't help. So this year we called professional cleaning for those 2 ACs. The guy spent 1.5h on each, disassembling, washing. Circuit board on AC is bigger than on my laptop. I swore that my next apartment will have the dumbest ACs.
So the last few days were hot, and we tried those ACs again and the smell is still there, at least 50% of it. Very disappointed.
Is it normal? What am I doing wrong here? I've lived in much older apartments and never had such smell even without professional cleaning.
NOTE: In winter there's no smell at all in heating mode.