It takes about two days for the advanced app clip experience to work once the full app is accepted for distribution. And it still doesn't work on some devices. I think it's a CDN cache issue, maybe some of Apple's servers around the world haven't updated the data. In previous builds, we have tried a few different Associated Domains configurations because we don't know which one is right. If the issue is caused by caching, the appclips:public.pisenpower.com part, in the full app target, may not be needed. Since it works now, we will still leave it there.

It works now. We did nothing, all the config is the same. I guess we just have to wait. Scanning the QR code finally opens the app clip card. We tested on a few devices, sometimes the app clip icon doesn't appear in the camera view when scanning, maybe it's a network issue. The Advanced App Clip Experience status is still Received, but the App Clip Diagnostics have all green check marks. It looks like the Advanced App Clip Experience will only take effect if it passes the diagnostic tests. Received status doesn't guarantee that. And the status doesn't need to be in something like Published which is referred in other forum threads.

From Your Website section from different iPhones now have the same results. It's caused by redirection when accessed from USA (Our server side implemented this). The redirection is removed now.

Additional: scan the QR code can open the full app if it's installed. Our app name is Pisen, which is available in all countries.

Our full app is on App Store for a few days, but the App Clip Experience is still at "Received" status. The App Clip Diagnostics states that "No Advanced Experience is registered for this URL." We cannot open our app clip by scanning QR code of our advanced experience URL.