Slime Farm Issues

I need help because I want to build a slime farm I have found chunks using a slime chunk finder. I have built it below level 40 at 35, It's a 16 by 16 area and I have triple checked my coordinates and seed. I have placed jack o' lanterns spaced out on it. It is in fact 3 blocks tall. I at one point left the area more than 25 blocks away and less than 40 for about 4 hours! and not a single slime has spawned. What can I do or what am I doing wrong.
Best Answer
If you've found this slime chink in a Swamp biome, they will spawn between layers 50-70. However, everywhere else they will spawn below layer 40, so you should be fine there. You'll need to be between 25 and 32 blocks away. Assuming you've met all of these—the slimes should spawn. Of course, I'm assuming you are playing on a difficulty other than peaceful.
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Why is my Minecraft slime farm not working?
If you have seen a slime, then very likely there are just too many other places for MOBS to spawn in the 150x150 region around you, that fill up all the MOB slots. Time to break out the torches, and start lighting everything around you.Why is slime not spawning?
Like most other hostile mobs, slimes do not spawn within 24 blocks (spherical) of any player, despawn over time if no player is within 32 blocks, and despawn instantly if no player is within the despawn radius (128 blocks in Java Edition, 44 to 128 blocks in Bedrock Edition depending on simulation distance [verify]).How far away should I AFK from my slime farm?
Remember, slimes only spawn if you are farther than 24 blocks away. Unfortunately, they will also despawn if you are more than 32 blocks away. With this farm, it's best to create a small area within this range to AFK in.What is the point of a slime farm?
Slime farming is a method of automatically spawning and killing slimes to easily obtain slimeballs, which can be crafted into slime blocks.Game Changing Slime Farm 1.18+
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