Issues with packet sniffing with airodump

I tried to do the following airodump command:

airodump-ng wlan0

I got the following output.

CH  1 ][ Elapsed: 1 min ][ 2024-11-19 04:13 ][ interface wlan0 downBSSID      PWR  Beacons    #Data, #/s  CH   MB   ENC CIPHER  AUTH ESSIDBSSID      STATION         PWR   Rate    Lost    Frames  Notes  Probes

I was not able to view the list of active routers in the vicinity. Any explanation to this?