Thank you for reaching out to the Community! I'm happy to provide some assistance with locating an app that allows you to sell on Amazon, to ensure this gets resolved.
To successfully sell on Amazon via Shopify, you can check out the Shopify App Store. We have an available app called Shopify Marketplace Connect, that allows you to sell across top global marketplaces like Amazon, eBay, Walmart, etc. Please feel free to add this app to your shop, as it's free to download.
Please let me know if you have any other questions or concerns.
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