Washing clothes have never worked for me either...if I'm at Fairhaven.
It works if favourited and able to wear the set.
Also if you do not have sleep ware then you damage the day clothes ...
Also if you do not set auto equip clean clothes or wear sleep ware at bed, it will not get washed.(cause you wear it)
So the reason is tardiness
not bug.
There are bugs in game but it is not. It is just not noob friendly...also needs in game help.
To sum it up noobs do not know the system and cry out for help instead exploring the system.
All of this
can be automated under the blue icon(phone).
Outside F.H clothes can be washed by your wardrobe.
In F.H auto washed if not worn and fit the mc.