Click on your Company Name in the left Navigation panel.
In the drop-down, go to SetUp > SetUp Review Links
Fill out the URLs by editing Facebook Business Page
Step 1:
Click Edit Button
Step 2:
Enter URL here
Step 3:
Search for your Facebook Business Page and Copy it's URL. 
Step 4:
Click to EDIT or ADD the URL
Step 5:
Paste the URL here and Save. 