I created a mission in the editor, and I use "base" respawn with ticket system and "menu position" enabled; I placed different Respawn position Modules. However, when I play sometimes i can't respawn, because in the respawn menu it says "respawn disabled" where there should be the "respawn" button. I use in my mission also Ace 3 mod, and some playable units, through a script, receive one respawn ticket each time they respawn, so the problem is not related to a lack of tickets.
Edit: tried without Ace, issue still present.