Hi Hamza,
If your payload has a isSimulate boolean property with a false value the associated rule should execute. If the boolean isn't there however, I believe you'll need something like
$not($exists(message.body.isSimulate)) or message.body.isSimulate = false
Also note that request is immutable and thus cannot be parsed, but your initial parse which places into message.body a parsed object will also create a request.parsed_body in context if you ever need to refer back to a parsed version of the original request.
Best Regards,
Steve
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Steve Linn
Senior Consulting I/T Specialist
IBM
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