Sortd needs Desktop Notifications to be enabled in order for the Reminder functionality to work correctly. If when setting your first Reminder you block Chrome from allowing Desktop Notifications you will have to re-enable Notifications through the Chrome settings in order to proceed.
Click the Google Chrome Menu icon to the right of the address bar and then select the "Settings" menu option. Alternatively type "chrome://settings/" into your address bar. Click the "Show advanced settings...”
Click the "Content settings ..." button under the "Privacy" section.
The "Content settings" popup box should appear as shown below.
Scroll down to the section called Notifications
Click “Manage exceptions” and delete the entry in the list for “https://app.sortd.com” that is marked as Blocked., by clicking the little cross next to the entry. Click "Done" when complete and return to Sortd to be able to re-enable the Reminder notifications.