You may also need to take a cover off where the screwdriver slot is too.

It may also be necessary to use a piece of paper when doing so, so that you don’t scrape the chrome on the flushometer.

There also may be a tiny weep hole too, which is what is causing the suction to release and the vacuum to seal up, also causing the flushometer to not be able to stop running the water into the toilet.

Something very tiny in width should be used to clean the port of the weep hole.

Something very tiny in width should be used to clean the port of the weep hole.

Do you hear two clicks two seconds apart? If so, then you need to clean or replace the diaphragm kit. This kit is accessed by taking off the top of the flushometer. [5] X Research source