I have been having trouble with my Note10+ for the last 3 days where the moisture detected error has been on permanently. The phone is 11 months old and has never been in water or near water. I have tried all the suggestions including doing a factory reset but it is still there. I have had to buy a wireless charger to keep charging.
I have tried to back up some photos to mu USB stick but the phone does not even recognise it as well. I was wondering if the usb port could be faulty.
I had this with my S9+. Often it was just a bug but eventually Samsung replaced it. Now I have it again.
Personally, I will never buy another Samsung phone because of this. The phone is now almost 3 years old, and unusable when away from home (where at least I have a wireless charger). I would prefer to be able to override it and take this risk of it damaging the phone, then getting a new one if that happened. As it is I am left with a phone nannied into near-uselessness.