Mailchimp is not sending emails with discount codes

I've set up a campaign with Personal Discount codes in Mailchimp but emails are not being sent to customers.

1. Make sure that your campaign status in Mailchimp is Sending, and not Paused or Draft.

2. Check if the email filter condition for the discount code merge tag is is not blank. A common mistake to select the is condition and enter "not blank" as value.