Hello @XiP. If you would like to make changes to your saved template, you would have to create a copy of it first. Then, once you make your changes and sent the campaign, you can then save this updated template to your template picker. You will also want to make sure to delete the older template to keep them up to date. I will submit feedback for you in regards to being able to update a template without having to create a copy.
Caitlin M. Community & Social Media Support
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