Go to Online Store->Theme->Edit Language
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Elias here with Shopify Support. Thank you for reaching out.
If not, could you share the store address or a screenshot so that we can help guide you to the right place?
Thank you for the follow-up. By default, the store name is automatically pulled into the footer from your settings, unless this was changed in the theme's coding. You can try changing the store name under "Settings > General" and see if that gets reflected in the footer.
Let me know if this is what you were looking for?