Mobile phone ringing love: have this in despair? (2,4)
I believe the answer is:
no hope
'have this in despair?' is the definition.
(someone despairing is hopeless)
'mobile phone ringing love' is the wordplay.
'mobile' indicates an anagram.
'ringing' is an insertion indicator.
'love' becomes 'o' (love means zero in tennis).
'phone' anagrammed gives 'nhope'.
'nhope' placed around 'o' is 'NO-HOPE'.
(Other definitions for no hope that I've seen before include "A state of despair" , "Not having any chance of winning" .)