This kind of thing happened during the beta when people were creating their own designs for colony ships and constructors and then obsoleting/deleting the standard design. Did you did something like that?

I am having the same problem, but it started much later in the game (well past turn 200). I might have clicked it by accident, but I also noticed my default colony ships disappeared after I designed a different ship (is there an auto-obsolete kicking it?).  Is there an edit we can make to reverse a ship's "obsolete" state?

I had thought I remembered a fix during the beta for the problem of Draft Colonists not working if the default colony ship was obsoleted.  But clearly either I'm misremembering, the fix didn't work, or the fix subsequently got reverted. Hopefully the devs will look into it, I'll bring it up on the Discord chat.

In the next update you won't be able to obsolete colony ships anymore to prevent this issue.