My username is: brayden2342 The bugs on skyblock 1 and nothing spawns. I have had the spawners in a ender chests and just placed them.
What kind of spawner is it? If it is for cows or sheep there has to be grass underneath. If it is for squid it has to be in water, if I'm not mistaken.
Maybe it's so laggy the mobs won't spawn or you are too far from the spawner. If you are spawning peaceful mobs: 1. There must be a flat layer of grass blocks and put the spawner on the middle of the grass block. If it's harmful mobs: 1. Create a flat layer of cobblestone or other blocks and put the spawner.