Hi,
You could try cleaning the port with 98-100% isopropyl alcohol.
Web search how to do it safely.
But if after getting the water detected warning and giving it time to dry out, it’s a fair bet you will need to replace the charging port or have it done by a repair shop.
The phone will still function without replacing the port but as time goes by internal corrosion may start to affect other components on or near the charge port if the original immersion rated seals have been breached.
Hope this helps