I found that the webhook can't be running properly if using shopifyAuth method to authorise the app. The webhooks is registered successfully and receive the response from shopify. However, it alway show "Failed to process webhook: Error: No webhook is registered for topic app/uninstalled". I tried use both Graph / Rest API to register the webhooks but the result are same. After compare the demo program, the only difference is createShopifyAuth. The demo program is using createShopifyAuth but i'm shopifyAuth (refer to the koa-shopify-auth same code) . Anyway, the problem was resolved once using createShopifyAuth.
But, i was wondering if anyone using "shopifyAuth" and successfully subscribe and got response from Shopify? Thanks.