Hi, I'm having the exact same issue here.
I've scanned through some previous threads, and it seems like those bats have ridiculously small hit boxes, so you just have to use some AOE skills to deal any damage to them.
I've just given up being an archer and switched to a mage because those bats were SOOOOOOO irritating.

Looking forward for fixes.

Yes its irritating. Bats and rats :-)

This bug is on top of other bugs, due it makes gameplay completely useless.