A network in dispute (2,5)

I believe the answer is:

at issue

'in dispute' is the definition.
('at issue' can be a synonym of 'in dispute')

'a network' is the wordplay.
'network' becomes 'tissue' (I have seen 'cellular network' mean 'tissue' so perhaps 'network' could also mean 'tissue').
'a'+'tissue'='AT ISSUE'

(Other definitions for at issue that I've seen before include "Questionable" , "In question, under discussion" , "Being discussed or disputed" , "in dispute" , "under debate" .)

I've seen this clue in The Telegraph.

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