NPC Limit Not Working

Summary

I made some NPC spawner, I just did a limite of one spawn per spawner but the limit is not working at all, sometimes it spawns 2 npc sometimes 5 and they can spawn under the ground.
I blocked all the limit to only 1.

Please select what you are reporting on:

Creative

What Type of Bug are you experiencing?

Assets

Steps to Reproduce

Try to set the limit to 1 spawn m

Expected Result

Only 1 spawning

Observed Result

2 to 5 npc spawned

Platform(s)

PC

Island Code

7112-5877-8260

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