Creeper farms do not work, or only spawn spiders.

I need one so i can create a tnt machine for help me find some diamonds/netherite,

And as i cannot get a working creeper spawner, which most videos only are for the java version, and i have that, but i mostly play on bedrock for survival mode.

Basically it seems that creeper collision boxes are too big, as big as the zombie/sekelton mobs, but the creeper is noticably smaller then them, i need a 2 block tall wall for it, and top half slabs for the roof.

I do not know why, but it works fine on java, if this bug could be fixed soon i would be very greatful.