Nanobeam 5ac Gen2 led problem

Hi to all,

I installed the latest nightly build (23.5.XXXX, to avoid the permanent memory problem) on the nanobeam. I'm using it as wi-fi client. It works well.

Some technical data of router and software:
Ubiquiti NanoBeam AC Gen2 (WA);
Atheros AR9342 rev 3;
Firmware Version: OpenWrt SNAPSHOT r24936-60ffcfdabc / LuCI Master git-24.025.10336-0617d30

I installed the luci-app-ledtrig-rssi module to configure the wi fi signal strenght leds, but the leds still don't work.

That's my system file

config system
	option hostname 'vivo3782'
	option ttylogin '0'
	option log_size '64'
	option urandom_seed '0'
	option compat_version '1.0'
	option zonename 'UTC'
	option log_proto 'udp'
	option conloglevel '8'
	option cronloglevel '5'

config timeserver 'ntp'
	list server '0.openwrt.pool.ntp.org'
	list server '1.openwrt.pool.ntp.org'
	list server '2.openwrt.pool.ntp.org'
	list server '3.openwrt.pool.ntp.org'

config rssid 'wwan0'
	option dev 'phy0-sta0'
	option refresh '200000'
	option threshold '1'

config gpio_switch 'poe_passthrough'
	option name 'PoE Passthrough'
	option gpio_pin '3'
	option value '0'

config led 'led_rssilow'
	option sysfs 'blue:rssi0'
	option trigger 'rssi'
	option iface 'wwan0'
	option minq '10'
	option maxq '100'

config led 'led_rssimediumlow'
	option sysfs 'blue:rssi1'
	option trigger 'rssi'
	option iface 'phy0-sta0'
	option minq '26'
	option maxq '100'
	option offset '0'
	option factor '1'

config led 'led_rssimediumhigh'
	option sysfs 'blue:rssi2'
	option trigger 'rssi'
	option iface 'phy0-sta0'
	option minq '51'
	option maxq '100'
	option offset '0'
	option factor '1'

config led 'led_rssihigh'
	option sysfs 'blue:rssi3'
	option trigger 'rssi'
	option iface 'phy0-sta0'
	option minq '76'
	option maxq '100'
	option offset '0'
	option factor '1'

Thanks to all!

I made a dumb question?