What do I need to reseal the skylight.
Thank you
Some use Sika flex
Is it leaking or do you just want to replenish the flashing as PM?
Here is some info on the replacing the entire unit Replacing Shower Skylight (https://wiki.foreforums.com/doku.php?id=technical:exterior:skylight) it has some information on the frame to roof sealing that may be of interest to you.
Just PM measures
I used Surebond SB-140 a couple of years ago when I replaced my bathroom skylight. SUREBOND | SB-140 SKYLIGHT & WINDOW BUTYL SEALANT (https://surebond.com/SB-140/)
It stays soft and malleable and doesn't harden and crack like Dicor. Much easier to remove. I am using it from now on for any caulking that needs to be resealed.
Jerry