Based on the error message you're receiving, it looks as though your Instagram account is connected to another Facebook Commerce account.
If you need assistance with disconnecting the Instagram account from the Facebook Commerce account, you will need to contact Meta Support directly. This is because this issue is fully supported by the Meta platform. The Meta Support team is equipped to provide you with the necessary guidance, solutions, and resources to continue assisting you.
To get in touch with Meta Support, please select the Get Support button in your Shopify admin > Facebook Sales Channel section. You'll need to select the topic Accounts, connections and permissions.
If you have additional questions or concerns, feel free to share them here.
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