I tried to summon the raids on a normal terrain
Are you raised off the ground like on a 2nd story. i have sky base for fighting but you literally have to be on the grass touching grass to start a raid.. even if only 1 story height the raid wont start. because it cannot track your position location correctly. as image shows is my raid base
do you have any prevention totems up, like the grass man. there is prevent raid stuff in plant workbench, & will prevent raids
when you try again look in top left corner of screen. did it say "Raid did not occur". < this is normal, but it also good way to know, if they cannot track you . it cannot create & find suitable path to get to you... or say "distance clamor 30+blah blah" Giving you raid details, & in that case, game maybe bugged if they don't come