I had a high water bill and did the dye test. It did leak into the bowl so I replaced everything in the tank. Everything was fine. I have now received another high bill and tried the dye test again. It leaked into the bowl again. I then waited and turned off the water source to the tank (making sure tank was full first) and none of the dye leaked into the bowl. What is my problem now?

What is the water level in the tank? Could the fill valve be overflowing the overflow pipe? You said you replace everything, did you replace the fill valve?

The water level should be about 1" below the top of the overflow pipe when the fill valve shuts off?

If turning off the stop valve stopped the dye from going to the bowl, that sounds like the fill valve is not completely stopping the flow of water.