If you're experiencing any trouble with sending an email, below are some of the common problems that you may be facing:

Automation run every hour to check for new customers

A Segment is always updated in real time so you will always be looking at the right group of customers matching your segment criteria. However, Marketing Automation running on any segment is hourly updated, which means that every hour, Automation check the segment to add new customers to its workflow.

Your Segment Criteria applies to no one

Check if the Segment has any customers in it. Just go to Customers > Segments and check whether any contacts are placed in it. 

Check Stats for your Automation Steps:

Check the running Automation (the one you created, for example, for order follow-up).

If the Automation has any emailing steps with zero stats, then the Segment might have been empty at the time the step was scheduled to run.

If the Automation has any steps with non-zero stats, you need to Contact Us

Customer doesn't Accept Marketing

Check if your customer opted in for marketing. Customers tend to uncheck the “Accept Marketing” checkbox during checkout. In Shopify, BigCommerce, or WooCommerce Admin, please check the Customers > Accepts marketing tab. This lists your customers who opted-in to receive marketing emails.