Bug on trying to add product to favorites.

Trying to Add a Product from the Market to my favorites, it returns "null" and it is not added to favorites.

• This is happening in https://www.una.io so we think this might affect all customers who have this module installed as well. 
• We have not tested to reproduce this error in other servers.
• Screenshot is self explanatory, but we can explain further if needed.
  • Steps to reproduce the error:
    • Go to a Product page in Market Module
    • Click on "Favorite" Button
    • The button does nothing
    • If you open the Chrome Web Console and click on "Network" tab then click the link "favorite.php?..." you will see the value returned is null.

Alex T⚜️ 

MSolutions