I have a situation in a bathroom. When you flush the toilet, all the water in the bowl does not drain. I took the lid off the tank and flushed it again. I noticed that when I depress the handle the water in the tank begins to empty as the flapper opens but it closes too quickly to allow a full bowl of water to pass. If I hold the handle down for an extra two to three seconds, it works fine. The flapper just closes too quickly. My cousing did something to it over the weekend ( he adjusted the float a little lower to stop the water from running). I don't know if that had anything to do with it. Please help me!!

Thanks,
Parrothed36