Villager wakeup on block above the bed

I included some screenshot for better visualization.

 

So as you can see the villager doesn't wakeup on top of bed and wakeup on block (glass) above it but somehow i fixed it (villager on the left) by removing the block directly above the bed and let the villager wakeup on top of bed and it managed to work after a few test going back and forth day and night.

 

Thanks.