His older TV's repair is not long-lasting (5-5)
I believe the answer is:
short-lived
'not long-lasting' is the definition.
(something short-lived doesn't last long)
'his older tv's repair' is the wordplay.
'repair' indicates anagramming the letters (letters are fixed or repaired).
'his'+'older'+'tv'='hisoldertv'
'hisoldertv' is an anagram of 'SHORT-LIVED'.
'is' is the link.
(Other definitions for short-lived that I've seen before include "Lasting for a little time" , "Lasting briefly" .)