Soldiers being insincere, showing uncooperative attitude? (8)

I believe the answer is:

reacting

'showing uncooperative attitude?' is the definition.
(reacting rather than going along with something)

'soldiers being insincere' is the wordplay.
'soldiers' becomes 'RE' (Royal Engineers).
'being insincere' becomes 'acting' (putting on an act).
're'+'acting'='REACTING'

I've seen this clue in The Telegraph.

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