It is very important to make sure that the o-rings on your Paralenz Vaquita are intact - otherwise, the camera will not be watertight.
There are 3 o-rings located on the inside of the end cap. You can check that there is no hair, dust, or debris on them.
If you need to take the o-rings out, it's important to use a wooden tool - to minimize the damage.
Once this is done, you can make sure that the o-rings are not damaged (tears, chips, etc.) and they can be cleaned directly.
It's important that the o-rings have a very thin layer of grease on them (so they are always shiny). Please note, that putting too much grease can result in the camera no longer be watertight.