ejabberd_system_monitor:send_message not working in iq handler

Dear All,

I want to send message from server to a specific user or groupchat in a iq handler by using ejabberd_system_monitor:send_message(From, To, "Message", []),

But the message is not send to the user and there is no error at all.

where the message gone ? is it the right way to send message from server to client in iq handler ?

Thanks.