Greetings. Am i doing something wrong?

I created a Testworld in Singleplayer (Flatland)
My Bedrock is on 0 and i place an Obsidian on height 1.
I drop some redstone on the Bedrock that is next to the obsidian.
With an Empty Hand i Left Click the Obsidian 1 time and nothing happens.

What am i doing wrong?

There should be a space between obsidian and bedrock, so bedrock is 0, obsidian is 2

ah ok now i got it, that worked. Thx very much