Outbound Proxy Error

This morning the asterisk log files were dominated by these errors:

[2015-08-24 09:59:35] ERROR[9549]: res_pjsip/pjsip_options.c:347 qualify_contact: Unable to apply outbound proxy on request to qualify contact sip:[email protected]:5065
[2015-08-24 09:59:37] ERROR[9549]: res_pjsip/pjsip_options.c:347 qualify_contact: Unable to apply outbound proxy on request to qualify contact sip:[email protected]:5063
[2015-08-24 09:59:38] ERROR[9549]: res_pjsip/pjsip_options.c:347 qualify_contact: Unable to apply outbound proxy on request to qualify contact sip:[email protected]:5065
[2015-08-24 09:59:41] ERROR[9549]: res_pjsip/pjsip_options.c:347 qualify_contact: Unable to apply outbound proxy on request to qualify contact sip:[email protected]:5062
[2015-08-24 09:59:43] ERROR[9549]: res_pjsip/pjsip_options.c:347 qualify_contact: Unable to apply outbound proxy on request to qualify contact sip:[email protected]:5062
[2015-08-24 09:59:44] ERROR[9549]: res_pjsip/pjsip_options.c:347 qualify_contact: Unable to apply outbound proxy on request to qualify contact sip:[email protected]:5060
[2015-08-24 09:59:46] ERROR[9549]: res_pjsip/pjsip_options.c:347 qualify_contact: Unable to apply outbound proxy on request to qualify contact sip:[email protected]:5062

With these we had server errors on the phone

Can anybody tell what might have changed?
Or where I might need to look?

Hello! How you solved your problem?