-- Executing Dial("SIP/1-e1a8", "Zap/1/5571703") in new stack
Apr 14 21:08:54 NOTICE[3553]: app_dial.c:1029 dial_exec_full: Unable to create channel of type 'Zap' (cause 0 - Unknown)
  == Everyone is busy/congested at this time (1:0/0/1)
    -- Executing Congestion("SIP/1-e1a8", "") in new stack
  == Spawn extension (local-access, 5571703, 2) exited non-zero on 'SIP/1-e1a8'
Apr 14 21:08:54 WARNING[3524]: channel.c:787 channel_find_locked: Avoided initial deadlock for '0x8146190', 10 retries!