In all the mob farms that are located at heights greater than 30 blocks, no zombies spawn, instead more skeletons spawn, the same happens in caves, no zombie spawn, only on the surface spawn zombies. But all other mobs Spawn on all surfaces. Anyone type of zombie Spawn in caves or mob farms. Instead, the Spawning of skeletons in caves and mob farms increases too much.
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Thank you for your report!
We're actually already tracking this issue at MCPE-71684, so I will resolve and link this ticket as a duplicate.
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