techdevil - you provided us your airodump-ng command, which is incorrect by the way (you left out the monitor mode interface). Also did you put your card in monitor mode on the target AP channel before issuing the airodump-ng command?
This will put your card in monitor mode and you will see notification that monitor mode was created on mon0 or similar. They you should type:
airmon-ng start <iface> <target channel>
NOTE: the "mon0" at the end of the airodump-n command is the monitor mode interface created by the arimon-ng start command. the airmon-ng command output will tell you which monitor mode interface was created and you need to use that info in the airodump-ng command.
airodump-ng -c <channel> --bssid <target AP MAC> -w <output filename> mon0