Can't kill animals on Minecraft server?

I recently tried to farm a bit on my server in the farm world and wanted to kill a few animals to farm food.

Then I noticed that this was not possible because I couldn't beat her.

Does anyone have any idea how I can solve this problem?

(I installed essentials and Multiverse Core if it could be related?)

Then you were classified as a vegetarian!

Could one that with MultiVerse-Core in the worlds can set the PVP is off I could still imagine.

Thanks but how can I change that? : /

Just found it, but PvP was true

Then I don't know sry