FujiFilm WP-FXA500 Owner's Manual page 41

If foreign particles cannot be removed ...
If foreign particles cannot be removed;
➀
Remove the waterproof sealing.
➁
Gently wash the foreign particles off the waterproof sealing with water.
➂
Wipe off the water droplets carefully using a soft, lint-free piece of cloth
or something similar.
➃
After the waterproof sealing is dry, install it into the waterproof case.
Remove the waterproof sealing with your fingers, taking care not to damage
it. Do not use a pointed object, metal, etc.
Do not pull on the waterproof sealing forcibly; a stretched waterproof sealing
may impede closing of the waterproof case, or cause a water leak.
When installing the waterproof sealing, make sure that it is evenly seated
without twists.
When installing the waterproof
sealing, match the projection of the
waterproof sealing with the dimple
of waterproof case.
Install the waterproof sealing,
pressing down all around to seat it
firmly.
EN-17