Flushing toilet problem!?

I have a push button toilet. Recently the water was flowing into the bowl continuously but I discovered I could stop this if I unscrewed the button and wiggled the air tube. Very technical!! However, yesterday I accidentally pulled the tube off whatever it was attached to in the cistern so am using my shower to flush the toilet.
The problem is that I can only take off the front of the unit hiding my toilet so cannot see into the cistern to reattach the tube. I can put my hand in but don't know what I am feeling for or where it might be located!