If your ESC program device won't connect to your ESC, there may be an extremely simple fix. This comes up when your LCD box says "Connecting ESC" and won't move on, or your OTA and HW Link V2 App gives errors on connection.
Unplug your ESC, from the receiver and try again.
If the ESC gets any information from the ESC, it will "not" allow the programmers to work. This also happens, if the ESC has not been calibrated, or the radio is not turned on. If the ESC gets anything other than the neutral signal from it's calibration, it locks out the ability to be tuned by a programmer.
Typically if the ESC has been calibrated to the radio, and the radio is turned on the programmers will connect normally. If there are any problems, you'll still want to unplug the ESC from the receiver. Throttle trim changes, or basic throttle mechanism wear in the radio can cause issues.