what's wrong with my script for freedns.afraid.org ?

/ interface WAN2
{
:global ExternalIP
:local clientip
:local clientstatus
monitor External once do={:set clientip $“local-address”; :set clientstatus $status}
:if ($ExternalIP!=$clientip) do={
:log info “External IP changed from $ExternalIP to $clientip”
/ tool fetch url=“http://freedns.afraid.org/dynamic/update.php?<MY_KEY>” dst-path=ExternalIP.txt
:set ExternalIP $clientip
}
}

It is not work , not able to update . May i know how to do the debug?