If your website template contains a legacy store section (available with our legacy Online Store and Advanced Store plans), it may not allow you to unlock all the Business plan's features.
Don't worry, and simply remove that legacy store section by clicking on the trash bin icon in the top-right corner of the section:
If you struggle to find the legacy store section, make sure to check all your website pages by expanding the Pages and navigation panel on the left.
Once the legacy store section is removed, proceed with setting up your online store 🎉