1. Log in to your Merchant Center and navigate to the "Settings" tab
2. Scroll down to "Presence/Review Sites"
3. Click the "Edit" button in the top right-hand corner of the Facebook box
4. Paste the URL of your Facebook page into the field at the bottom
5. Click "Save Changes" in the top right-hand corner of the box
A direct link to leave a review on that page will generate upon saving.
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