Hi,

I installed Kamailio SIP server:
Following article: https://github.com/open5gs/nextepc/blob/master/docs/_docs/guide/04-setting-up-kamailio-IMS.md

By following step # 12 (as per above article) when we initiate the call we get - Too many hops 483

Created two user earlier:
$ kamctl add test testpasswd
$ kamctl add test2 testpasswd

syslog show:
Aug 27 09:36:50 localhost /usr/sbin/kamailio[56286]: ERROR: nathelper [nathelper.c:780]: add_contact_alias_0(): failed to get contact uri
Aug 27 09:36:50 localhost /usr/sbin/kamailio[56286]: ERROR: ims_registrar_pcscf [save.c:268]: save_pending(): No contact headers
Aug 27 09:36:50 localhost /usr/sbin/kamailio[56275]: ERROR: <script>: REGISTER (sip:test1@139.54.102.135 (139.54.102.135:5060) to sip:test1@139.54.102.135, ee24f837b04b07334e25befe81217f8f@45.45.0.16)

Aug 27 09:36:50 localhost /usr/sbin/kamailio[56275]: ERROR: nathelper [nathelper.c:780]: add_contact_alias_0(): failed to get contact uri
Aug 27 09:36:50 localhost /usr/sbin/kamailio[56275]: ERROR: ims_registrar_pcscf [save.c:268]: save_pending(): No contact headers
Aug 27 09:36:50 localhost /usr/sbin/kamailio[56276]: ERROR: <script>: REGISTER (sip:test1@139.54.102.135 (139.54.102.135:5060) to sip:test1@139.54.102.135, ee24f837b04b07334e25befe81217f8f@45.45.0.16)

Aug 27 09:37:05 localhost /usr/sbin/kamailio[56278]: ERROR: <script>: REGISTER (sip:test1@139.54.102.135 (45.45.0.16:42965) to sip:test1@139.54.102.135, 04e06b6352f7a2b8f97c1a3733b3334a@45.45.0.16)
Aug 27 09:37:05 localhost /usr/sbin/kamailio[56278]: ERROR: ims_registrar_pcscf [save.c:339]: save_pending(): Will save pending contact without security parameters
Aug 27 09:37:05 localhost /usr/sbin/kamailio[56374]: ERROR: <script>: Diameter: AAR failed on subscription to signalling

Server IP 139.54.102.135 where Kamailio is installed, UE IP address 45.45.0.16, 45.45.0.1

Followed this https://www.kamailio.org/wiki/tutorials/faq/main#why_the_sip_requests_are_repli

Thought to test using SIPp - installed and ran default command: ./sipp –sn uac 127.0.0.1  and  ./sipp –sn uac 139.54.102.135

Aug 27 08:51:32 localhost /usr/sbin/kamailio[56295]: ERROR: <script>: INVITE (sip:sipp@139.54.102.135:5061 (139.54.102.135:5061) to sip:service@139.54.102.135:5060, 2-60232@139.54.102.135)
Aug 27 08:51:32 localhost /usr/sbin/kamailio[56295]: ERROR: ims_ipsec_pcscf [cmd.c:507]: ipsec_forward(): Contact doesn't exist

The user sipp and service does'nt exist

Added user:
kamctl add sipp testpasswd
kamctl add service testpasswd  

Still same error:
Aug 27 10:52:17 localhost /usr/sbin/kamailio[56289]: ERROR: ims_ipsec_pcscf [cmd.c:507]: ipsec_forward(): Contact doesn't exist
Aug 27 10:52:17 localhost /usr/sbin/kamailio[56284]: ERROR: <script>: INVITE (sip:sipp@139.54.102.135:5061 (139.54.102.135:5061) to sip:service@139.54.102.135:5060, 977-61357@139.54.102.135)

Please advise.
Thanks and Regards.