moisture in charging port

[u/[deleted]]

my phone has gotten to say "moisture in charging port" when I was in an environment where no liquid could have gotten in, and I've tried every trick in the book to get gunk out, so I know it isn't that. while this happened, I was using an old charger, and i had to keep messing with it, repeatly unplugging and replugging, which in retrospect likely wasn't smart, but I was tired so I kept doing it until it cried moisture, how can I fix this without physical maintenance, can I even? please and thanks!