If you have come this far you might want to verify that your front end implementation is set up properly. Or maybe something doesn't feel just right. Please follow below steps to verify or trouble shoot the integration. To get started, open up the developer panel in your current browser and go to the tab showing network requests.

Config Endpoint

Make sure the request against /api/v1/config/your_brand_name is returning 🟢 200 HTTP response and returns a JSON object and just not null.
If this endpoint is returning 500 response or null the problem lies on Fast Tracks side, please contact your Integration Manager.

Login Endpoint

Make sure the request against /fusion-api/Platform/LoginAuthToken is returning 🟢 200 HTTP response and that the response property Success has the value true.
If the request is returning another HTTP response code than 200, please contact your Fast Track Integration Manager.
If the request is returning Success: false please make sure your Authentication Endpoint on your Operator API is working as intended. If it is, and this request from the front end is still not working as it should, please contact your Integration Manager.

Getting Notifications

Make sure the request against /fusion-api/Notifications/v2/user-notifications is returning 🟢 200 HTTP response and that the response property Success has the value true. Don't worry if the property Data is just an empty array, that's just because the current logged in user doesn't have any On Site Notifications or Rich Inbox messages yet.
If above endpoints (config & login) are working properly this endpoint rarely fails. If you are sure that current user should have received notifications but the endpoint returns an empty array the "problem" is within Fast Track CRM. Problems could be that the user you're trying to send to is opted out for On Site Notifications, or the user could be blocked. Search for current player in Fast Track CRM and make sure he is not opted out for on site notifications or that he is not blocked.
If the problem still persists after debugging above, please contact your Integration manager

Pusher Front End Authentication

Lastly, make sure that the request against /fusion-api/external/pusher/your_brand_name is returning 🟢 200 HTTP response and that there is a response property called auth with a value.
If this endpoint is returning something else than described above, the problem lies within Pusher authentication. Please make sure your Pusher account is still active or haven't reached some threshold. Also make sure you sent the correct Pusher credentials to your Integration Manager.
Talk with your Integration Manager so they can make sure your Pusher credentials is configured correctly on Fast Tracks side.

Verifying the Front End Implementation

This is the bare minimum for the javascript front end implementation to work.