Hostapd_cli fails to connect to hostapd

I'm having trouble using hostapd_cli:

root@lede:~# hostapd_cli help
Failed to connect to hostapd - wpa_ctrl_open: No such file or directory

For clarification, hostapd is running in the background (wpad hostapd hostapd.conf), and I can successfully connect to the router via WiFi.

Following, I rebuilt the image using wpad in place of wpad-mini, and I'm still having the same error.

Has anyone encountered this issue before?

add ctrl_interface_group=0 in will start working.