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Marketo Smart Campaign fails to perform 'Send Email' flowstep and raises 'Failed: None.get' error
Our team has created a Smart Campaign to send out emails, based on several simple choices. Although the Smart Campaign seems to work, Marketo raises a 'Failed: None.get' error for the 'Send Email' flowstep:

Has anyone experienced this particular error before? Because Marketo doesn't provide any additional information about the error.