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Webhooks are processed asynchronously. This means that the service will return a 202 Accepted message before attempting to run the functions that you have written. As of 5.5.2, this can be modified. To have a webhook process Synchronously, and return a 200, 404, or 500 depending on what happens while executing it, send in the Header "flex-sync-webhook" with a value of "true".
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