You still have a leak between the well and the pump. Depending on how much air is in the line, pressure testing with air is much slower to show a drop than pressure testing with water. How many gallons of drawdown does it take to turn on the pump?
Maybe the footvalve is leaking again. Just because it was replaced twice does not rule it out. If you are having to flush crud out of the tank, crud might be preventing the footvalve from seating well.