Toilets, Sinks, Showers, Tubs and Disposals - toilet mystery

Hi. My powder room toilet is weird. The water in the tank during the day fills up above the water line that has been set. The toilet flushes properly and the tank fills up to the set line, but later in the day the water is again higher than the set line. Tested for leaks in tank, and ok. A plumber earlier in the month put something new in tank. Also, hear tap, tap, of water, not sure if in wall or sound echoing off walls. Luckily, no water is leaking. Also, when I first moved in found the toilet not bolted to tile floor properly, it was rocking back and forth. Just moved into place a couple of months ago. It's a townhouse. Could my place be effected by others?

lindylou785, Welcome to the DIY Forums.
It is probably a bad fill valve. It is possible, but unlikely, that when others use water the pressure is eased up on the valve and it opens. I would just replace the fill valve with a Fluidmaster 400A fillvalve. About $6 at Home Centers. Really great installation instructions come with it. Easy DIY job. Good luck.

Thank you for the suggestion. I think the plumber just put in a new stopper thing in the tank. What about the noise I hear that is echoing? Also, I'll ask neighbours if they have had similar problems with water. The good news is that I don't have water overflowing. Merry Christmas to all!

the noise you hear is the fill valve leaking through the overflow pipe