To stop calling - indication of broken engagement! (4,3)

I believe the answer is:

ring off

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'to stop calling' is the definition.
(as in to ring off a phonecall)

I can't explain the remainder of the clue.

(Other definitions for ring off that I've seen before include "Engagement over" , "sign engagement's terminated?" , "Slam down phone" , "Hang up" , "End a phone call" .)

I've seen this clue in The Irish Independent.

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