take the lid off and see if the handel is hooked on to the lift up bar, if it has came unhooked, it will feel free when you are flushing it, just hook it back on, try flushing it just by pulling up the hooked rod, and see how it works, sometimes the cisten digfram , becomes ripped, and it dont lift the water up to flush, if so you need a new one,
x, March 2014