I'm new to mapmaking and am trying to get my zombies to spawn for the first time

I've been following a YouTube tutorial

Zombies are not spawning here's what I've done

*set spawners
*set volume
*set kpv's

I am getting th...

first time making maps

pair "undefined" and "zombie door" has unmatching types
 "undefined" and "string"

not sure what this means, ive tried removing the zombie doors and it still gives this error

any help would be awesom...