Hello @DatumA. Thank you for coming into the Community. In order to make changes to a sent campaign, you need to make a copy of the campaign so you can then make any edits to it. From there, you can schedule the email to your list of Did Not Opens.
Caitlin M. Community Manager Did I answer your question? If so, please mark my post as an "Accepted Solution" by clicking the Accept as Solution button in the bottom right hand corner of this post.
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