Pixhawk4 firmware

hello and good day
I did a update for pixhawk 4, problem after update

  1. After reboot the pixhawk 4 keep beeping
  2. Unable to setup
  3. I tried few times reload the firmware same error
    4… Reload the firmware with dev master it beep few times than stop able to setup but cannot arm or fly
    and no error msg, . before the update the drone can fly as normal

need help…tq