I am building a custom app which handles shipping rates and fulfilment for a demo Shopify store. I have completed the shipping rate parts but am having issues with the fulfilment part. I am following this documentation: https://shopify.dev/apps/fulfillment/fulfillment-service-apps/manage-fulfillments-as-a-service-app
I have registered a fulfilment service. I've then associated all products with this fulfilment service and have created shipping rates using the fulfilment service that was created using the shipping rates from my custom app.
I can go through the checkout, get shipping rates from my custom app and complete the order. In the demo store's admin panel I can go to the order and click on "Request Fulfilment". The order then changes the status to "In Progress" and "Requested" but according to the documentation I'm suppose to get a request to my callback_url with "FULFILLMENT_REQUEST". I've put logging on my app on this callback URL but it doesn't seem to get hit. I've tried this with both GET & POST but the custom app is still not getting hit.
I've also tried the callback endpoint using the Postman software and I'm getting the request logs on the custom app.
Please can anyone suggest what might be the issue or if I'm missing a step to set this up.
Thanks
