Looks like it will only ring the first registered endpoint in the list. The one with "rinstance" is the registration is form the Sangoma Mobile app and the second one is the desk phone. If the desk phone is the first one in the list then it will ring that one.
Not sure if this is can be fixed?
Endpoint: 100/100
InAuth: 100-auth/100 Aor: 100
Contact: 100/sip100@159.xx.xx.xx:64478;rinstance= xxxxxxxx Avail 71.162
Contact: 100/sip:100@24.xxx.xxx.xxx:5060;ob xxxxxxxx Avail 27.120
