I used my elytra to get on top of a spruce tree and went into a crawling position in between the leaves and chopped the logs with an axe but 5 blocks down the block would not break. I could reach it.

What I expected to happen was...:
I can reach the block and break it. It should have broken normally and dropped the block.

What actually happened was...:
The block continuously broke and did not drop. 

Steps to Reproduce:
1. Use elytra or trapdoor to get into the crawling position
2. break the block in front of you downwards. Do not break the block under you. You should not fall down in the process.
3. ...