The {{{coupon_code}}} tag will work in the campaign email only if the coupon campaign is attached to the Mass Notification / Signup / Anniversary campaign.
To attach the coupon code to the Mass Notification / Signup / Anniversary campaign, please refer to the article How do I attach a coupon campaign to a Mass Notification or Signup / Anniversary campaign?
Disclaimer:
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This additional disclaimer will be removed upon formal review of this article. The standard Punchh Inc. KB Disclaimer still applies, and can be found at: https://support.punchh.com/hc/en-us/articles/360040100273-Punchh-Inc-Knowledge-Base-Disclaimer
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