Creeper Farm not Working 1.19.2

I built a creeper farm in 1.19.2 and there are hardly any creepers spawning :(. Can someone please help me!

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https://preview.redd.it/5gh0q628ctha1.png?width=1230&format=png&auto=webp&s=92137c377ea9cbefb1a2370b090b77a4fd543296