Roon cannot find UPnP device (Devialet Phantom Classic)

I have the Roon core in Asustor AS6302T, and with DOS2. I think I did connected the Phantom with Roon Remote thru upnp from iPad once…
But not anymore now…
I think it can search the Phantom as upnp in the “other network device” list together with the Airplay options. You can choose to use airplay or upnp.
But after a week or so for not using it, it is gone…
I use the Phantom is not for 16bits, that’s why I don’t want AirPlay at all!!
I use Roon is because it can play my DFF file while other media server thru Mconnect won’t.
But now the Roon get me a combined problem, play DFF at 16bits AirPlay…
Please help for a way to keep the upnp live.
Thanks