The screenshots in this tutorial show Chrome on a PC, but the process is exactly the same (and looks very similar) on a Mac. 

1. In Chrome, click the three dots in the top right-hand corner and select "Settings"

2. From the menu at left, click "Privacy and Security" 

3. In the middle section of the screen, click on "Site Settings"

4. Select "Cookies and Site Data" 

5. Turn "Block third-party cookies" OFF and 

    "Allow sites to save and read cookie data" ON

6. Quit the browser and try again. 

If this does not solve your problem, please feel free to reach out to for further assistance.