Why does my toilet flapper stay start? My toilet had a problem with intermittent running, which I determined be...

My toilet had a problem with intermittent running, which I determined be caused by a leaking flapper (the dampen level would drop, and the toilet would run to return the level to normal). I replaced the ring and the flapper (twice, two different models), but I hold the same problem- the flapper opens, but does not close when the flush is complete. So, unless I begin the tank and close it manually, it remains open and the dampen keeps running.

I haven't ever had this problem, and I put a foreign ring and the old flapper on, and tried two other models of flapper, same problem. This has GOT to be a simple fix, can you donate me some suggestions? I have tried adjusting the cuff length, too.

Thanks!
The heat contained by our house broke down....
most new flappers come near a "ring" on the back of it along with two "ears" near holes in them. if your flush valve stem that the flapper hooks onto have two pegs for the "ear holes" try cutting the ring out!! it may be keeping your flapper from seal and flowing correctly!! good luck
Dumb ask...BUT ANSWER IT!?
if you have a 1.6 gallon per flush toilet and you put surrounded by a flapper for older style toilet, that may be problem. get flapper for 1.6 gal toilet... another create could be too much water flow entering tank.at tap on lower left of tank turn clockwise to slow flow of dampen into tank
A paint query.?
The flapper is going back too far. There are vastly small notches that control how far the flapper can go support. It should not be vertical. Probably what happned was when you replaced the flapper those little notches be broken or you broke them. You can fix that with a glass top to a jar. You put the jar within the tank behind the flapper so it can't step back too far. There is another thing to you can do too, adjust the secure so it does not pull the flapper up too far. If nothing works after get a plumber to replace the whole collar. This is a undertaking for an experienced person. You don't want to risk the toilet overflowing or worse.
Combi boiler leak!?
Almost without a doubt we'll agree something is flaccid up on the flapper which could be as simple as taking it back off and "carefully" enlarge the two holes it attaches to the tube then use some Vaseline petroleum jelly or something similar to lubricate it and reinstall. Be sure the plastic fill tube is straight up & down and not orientated off center, if it is, loosen and retighten it.
AC leak on subflooring.?
Answers:    well they come with 2 hookup points. any a ring or they have 2 i guess you could call them handle. if you use the handles cut out the ring. this will fix your problem
Solar Panel HELP?
check the handle and variety sure it hasn't turned or loosened up also check the two pivot points on the flapper to make sure they are not binding if all else fail heres an old trick i have have to use on occasion remove the flapper turn it over and gently squeeze a quarter sized washer inside the heavens bulb the extra weight may be just plenty to stop the problem
What is wrong near my garage door introduction?
Too much travel make the chain longer, so the flapper doesnt come up too elevated. Flapper only needs to cone up enought to break the stamp, boyancy does the rest