iPhone 7 Plus Water Damage. Phone is working except for Touch Screen.

Yesterday, my iPhone 7 Plus got a dip in the pool not too deep. So after it got out of the water. We quickly dried it up so water couldn't get even further. Dried the speakers and Lightning Port. After some time. I noticed that my screen loses it's sensitivity. Sometimes it doesn't respond but still works it just hangs. Today, my iPhone 7 Plus is still working except for the touch screen. Haptics are still working. I just couldn't access the phone because it needs a passcode. I've done a bit of research on this phone to check whether it suffered water damage. Tried to check the water damage indicators and I noticed on the sim tray it did have a red indicator.

How am I gonna try to fix this? I also read that it wasn't covered in warranty. If there's another way, please tell me.