thank 4 ur reply.
I foud the solution.
I ever connected the hidden SSID before it is setted to hidden,so the SSID is in known networks list.
I deleted the hidden SSID in known networks list, and used connect-hidden hiddenNetworkSSID again.
It works!
[iwd]#known-networks list
hiddenSSID …
[iwd]#known-networks hiddenSSID forget
[iwd]#station wlan0 connect-hidden cloudsomersault