[SR-Users] 407 Proxy Authentication Required

Hello, I'm trying to implement Kamailio IMS and registration by using Boghe IMS. Registration profiles are default profiles provided by FHoSS ( Alice & Bob). While trying registration, I am facing some problems. REGISTER message behaves as intended and results with 200 OK. After 200 OK message, Boghe IMS is sending SUBSCRIBE message to S-CSCF (via P-CSCF), this message results with a 407 Proxy Authentication Required, I have some questions about this scenario. 1-) Why do I have this SUBSCRIBE message? Even though i commented out WITH_AUTH function, why do I have 407 Proxy Authentication Required message? 2-) On IMS Client side, when informaion about Alice or Bob is entered, login process results with success, but I can't send any message or do come calls. Is is related about this 407 message? 3-) On FHoSS interface, when I check IMPU values of those users, User-Status is marked as REGISTERED. From this perspective, should I consider registration is successful or not? 4-) How can I handle with this 407 Proxy Authentication Required message? Best Regards, Yağız --