Zoom and Polycom group 700 series codec

We have a couple of Polycom Group 700 series codecs. We are wanting to use them to dial zoom IPs and then join a Zoom call - by entering meeting ID and password through the polycom touch screen. We have a couple of Zoom IPs saved from previous session. We go in through the touch screen, select call and then search the favourites and select the appropriate IP. When we press call, the call is tried briefly but then "tjhe call has ended"  appears or it goes right back to the same screen. Nothing happens. In the past it would call and then Zoom meeting comes up asking to put in meeting ID and password - this is no longer happening. We are not doing anything through SIP, but have H.323 selected, We are also not using any of the backend polycom server technology as we had in the past such as RPM, RPAD, etc, I am not sure why this is no longer working. Is there something else I should be doing?