Doesn't stop, as it happens (4,2)
I believe the answer is:
goes on
'happens' is the definition.
('go on' can be a synonym of 'happen')
'doesn't stop as it' is the wordplay.
I cannot quite understand how this works, but
'stop' could be 'go' (going is a kind of stopping) and 'go' is found within the answer.
'as' could be 'so' (I've seen this in other clues) and 'so' is present in the answer.
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is found in the answer.
A single letter 'n' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Another definition for goes on that I've seen is " Continues".)