S20 Plus moisture problem tempory fix, but whats the real cause?

So my S20 plus has moisture problem detected thing for a while now. got the charging port replaced at a third party store and problem came back in a month.

went to Samsung store, and they cleaned my port and somehow it works for a few months.

moisture detected again, i opened up the phone, swapped out for a new charging port. no reception(i assume its fake). swapped back to the original and the moisture problem is magically gone.

So what i found out is, the moisture problem can be temporary fix if unplug and plug charging port cables. but it alway comes back after a week or so.

anyone knows whats is wrong?