I can't put coal,wood or anything in the bottom of my furnace. I've tried taping the bottom slot and it does nothing

Put the summary of the bug you're having here
I cannot put anything in the bottom slot of my furnace
What I expected to happen was...:
Describe what you thought should happen here
Well I tried turn off my iPad 2 and go back playing. I'm still having a problems
What actually happened was...:
Describe what happened here
I was trying to melt my gold ores and as I was done putting my gold in the top slot. I tapped the bottom slot and it did nothing.
Steps to Reproduce:
1. Get a furnace
2. ...and put anything that you can in the top slot
3. ...then try tapping the bottom slot