I have been trying to send an email containing Lead Report from sales cloud. The email when received shows the message "Failed" with an error report in the body. The error states "Error retrieving data". I followed the steps for sending report from trailhead. Linking the document here: https://trailhead.salesforce.com/content/learn/modules/marketing-cloud-connect/test-the-connection?trail_id=use-marketing-cloud-connect
If anyone has any idea as to why I am receiving this error, please help me out