If the leave a review / feedback link is not working, you should check that you set up the website integration providing the correct URL of your booking page. This is the page where customers are redirected to leave a review, or change/delete their bookings.
1. Go to Settings
2. Click on Website integration
3. At Point 2, verify that the URL of the page where you integrated the widget is correct.
You should change the URL of the page with the correct URL of the page where you integrated the widget.