4f55f5cb_ISDN_Cause_Codes__Cause_Usage
[Cause#] 27 [Fixit!] N/A [Cause Summary] Destination out of order. [Cause Usage] 
Indicates that the destination indicated by the user cannot be reached because the interface to the destination is not functioning correctly. The term 'not functioning correctly' indicates that a signaling message was unable to be delivered to the remote user: eg., a physical layer or data link layer failure at the remote user, user equipment off-line, etc.
ISDN Cause Codes
Cause Usage