Can't get Curl working with --interface $dev

Installing and Using OpenWrt
1

I'm trying to get $dev working through --interface $dev in Curl.

When trying I get curl: (28) Connection timed out after 5000 milliseconds

case "$dev" in
    tun1[1-5])
        
        sleep 2
		endpoint_ip="$(/usr/bin/curl -4 -sS \
                --interface $dev \     <<<=== this
                --connect-timeout 5 \
                --max-time 8 \
                https://api4.ipify.org 2>&1)"

            [ -z "$endpoint_ip" ] && endpoint_ip="unknown"

        else
            endpoint_ip="down"
        
    ;;
esac

Thats only when try through inteface, using eg othrer instance it's working just fine.
(eth1,tun10, tun11 and wgc1).

Have tryed with alot of testing but can't get it working.

@egc112
Do you have any thoughts and suggestions?