The upper and lower shell or hull and deck are separating in a few spots on the seam a Riot Tourlite 15 kayak. What do you recommend?

The upper and lower shell or hull and deck are separating in a few spots on the seam a Riot Tourlite 15 kayak. What do you recommend?

The  good news is that some good marine glue will fix this issue 

Apply a thin layer of Sikaflex 291 (or equivalent marine sealant/adhesive)  https://www.amazon.ca/Sikaflex-Multifunctional-Adhesive-sealant-Applications/dp/B004X7PEL6/

I hope this helps,