How to ensure you have the right unsubscribe link in your email template
First, you need to highlight the word "Unsubscribe" in your template. Then, click the insert/edit link button:
The way to make sure you have the correct unsubscribe link if you are copying the existing block or making any changes is to check that the URL is ##unsubscribe##. You can also go to the Special Links drop down and select Unsubscribe there to update the URL: