get interface allowed-channels from API

Hi to all,
I try to get allowed-channel from API without restults.

Terminal command is: “interface wireless info allowed-channels wlan1” and work correctly:

"
channels:5180/20/a…
"
but from APi I get no results:

<<< /interface/wireless/info/allowed-channels
<<< =interface=wlan1
<<<

!re

!done

someone has suggestions?

Thanks in advanced
Regards
Roberto