MY TOILET JUST BARELY LEAKS OVER THE ROUND OVERFLOW AT THE TOP. I'VE TRIED BENDING THE STEM UP AND THEN DOWN ON THE STEM HOLDING THE BALL, BUT IT MAKES IT WORSE. I'VE TRIED TIGHTENING THE SCREW ON TOP OF THE STEM, WHERE IT IS CONNECTED. MAYBE THE BALL IS GETTING TOO HEAVY OR SOMETHING (IT ISN'T HOLDING WATER INSIDE)ITS DRIVING ME NUTS!! (AND THAT'S NOT A LONG DRIVE).