In this first picture it shows a caulked skylight lens. This is not recommended. Over time the caulking fails and the skylight will leak again

Caulked Skylight Lens

In this picture it shows the reason why the sky light was leaking in the first place. If you look the “weep” (this is where the water comes out of the skylight). Has been caulked and foamed shut, blocking the waters exit. The water traped inside can only fill the trough and leak inside of the house.

This is the inside of the skylight

The operating function is as follows. Water runs in between the lens and the metal frame (see picture 1). Fills up in the trough. The water travels to the cornners and then out through the weep on the side. This skylight is ruined and needs to be replaced. At a price around $150-$200 or more depending on who does it!