sorry i dont know then, thats how i sell mine at my shop. i am using essentials signs.
mob_spawner:91 or whatever number..instead of 52:91
use mob_spawner:50 instead of 52:50. I dont have silkspawners installed, just using essentials.
I had this problem too, spent all day trying to figure it out, just happened to watch a video with a sign posted in the background. Dont use 52:91...
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