On this page, you will find more information about the most common causes and most relevant solutions for the Emarsys error '5009 - Event data is not valid JSON'. Do you need help straight away? Visit our support page.
The emarsys eMarketing Systems documentation indicates that error code '5009 - Event data is not valid JSON' is caused by the following problem: "External events triggers for which the event data is present but not parsable as JSON are not processed.".
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