Verbosity is at least 5
    -- Executing NoCDR("SIP/anonymous.invalid-081bfb20", "") in new stack
Aug  8 01:57:21 WARNING[23318]: cdr.c:443 ast_cdr_free: CDR on channel 'SIP/anonymous.invalid-081bfb20' not posted
Aug  8 01:57:21 WARNING[23318]: cdr.c:445 ast_cdr_free: CDR on channel 'SIP/anonymous.invalid-081bfb20' lacks end
    -- Executing Dial("SIP/anonymous.invalid-081bfb20", "SIP/NXXXXXXXXX") in new stack
    -- Called NXXXXXXXXX
    -- SIP/NXXXXXXXXX-6245 is ringing
    -- SIP/NXXXXXXXXX-6245 answered SIP/anonymous.invalid-081bfb20
    -- Attempting native bridge of SIP/anonymous.invalid-081bfb20 and SIP/NXXXXXXXXX-6245
    -- Got SIP response 500 "Internal Server Error" back from (sip provider)
  == Spawn extension (default, NXXXXXXXXX, 2) exited non-zero on 'SIP/anonymous.invalid-081bfb20'
    -- Saved useragent "Callctrl/1.6.0.0 MxSF/v3.5.3.4" for peer NXXXXXXXXX
localhost*CLI> sip show registry
Host                            Username       Refresh State
localhost*CLI>