We installed new hardware inside the toilet to stop problems we were having with the plunger system not shutting off the toilet as it refills. Everything worked fine for several months and then the the downstairs toilet started to keep running. Lifting the hood revealed that the flapper valve had not fallen into place thus all the water being put into the reserve tank was just running out. Jiggling the handle worked initially. Soon both toilets were having this problem and now it is to the point that we have to lift the hood on the reserve tank and nudge the flapper valve so it falls over the drain. I have tried adjusting the chain, shortening it, lengthening it, but nothing has worked. Any suggestions?