I use Asterisk 13.21.1 with PJSIP and realtime with MySQL, and I have an issue with Queue using Linear strategy.
[Jan 3 13:27:45] ERROR: res_pjsip.c:3188 ast_sip_create_dialog_uac: Endpoint ‘21025002’: Could not create dialog to invalid URI ‘21025002’. Is endpoint registered and reachable?
[Jan 3 13:27:45] ERROR: chan_pjsip.c:2226 request: Failed to create outgoing session to endpoint ‘21025002’
In the PBX the extension 21025002 are unavailable but the PBX continue trying to call when should get the next endpoint of the Queue.