network manager is not running after airmon ng check kill code example
Example: undo airmon-ng check kill
$> sudo ifconfig wlan0 down
$> sudo iwconfig wlan0 mode monitor
$> sudo ifconfig wlan0 up
$> sudo aireplay-ng wlan0
$> sudo ifconfig wlan0 down
$> sudo iwconfig wlan0 mode monitor
$> sudo ifconfig wlan0 up
$> sudo aireplay-ng wlan0