sync ringing between the Webex app SIP calls

sync ringing between the Webex app SIP calls and IP-phone registered to CUCM

We have the below scenario:

the user is on the Control hub and has a 1:1 non-PSTN license.
the user exists on on-prem CUCM
the calling on the control hub is "calling on Webex (Unified-CM)"
the user has an IP phone registered to CUCM

When the user receives a call on the on-prem DN, the Webex app and IP phone ring simultaneously.

But when the user got a Webex call 1:1 non-PSTN on the Webex app, the IP phone did not ring, only the Webex app rang.

Appreciate it if you could check the possibility to add integration between the two call environments so if the user gets a call on Webex "1:1 non-PSTN" in the Webex app, the call manager is aware of the call and ring on both the Webex app and IP phone.