In phone limbo (2,4)
I believe the answer is:
on hold
'in phone limbo' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for on hold that I've seen before include "waiting for reply" , "set aside for future use" , "Waiting for connection (telephone)" , "Temporarily set aside" , "Delayed -- postponed" .)