For a reward to be tracked in your user account, you will need to allow cookies. How cookies are enabled depends on your browser. This section explains how cookies can be enabled in the following browsers:
Click on the menu button at the top right corner (three dots).
Then click on "Settings"
Inside the section called "Privacy and security" click on "Site settings".
...and on "Cookies and site data"
Here you can set cookies to be allowed.
If you have the latest version of Firefox you can manage the cookies settings clicking on the small shield that you find in the address bar.
Once the pop-up window is open, you can click on "Protection settings".
Finally, make sure that you select the custom settings and deselect the Cookies option. That way, cookies won't be blocked in your browser.