I can't seem to place blocks and they disappear from my inventory!

They disappear and then I'm out of the block I was placing down. It's like the game is saying nope but I'm stealing your blocks.

What I expected to happen was...:
Placing a block to build.

What actually happened was...:
The block disappears and also disappears completely from my inventory.

Steps to Reproduce:
1. I don't know how it happened.
2. ...
3. ...