@tenna When did you upload your apple-app-site-association file? It takes a while for your device to retrieve rules from that file. However you can switch off the toggle and switch it on again to make it happen immediately. (Setting app>Developer>Universal Links)

When I trying to reach out via the support team email address provided in that mail, the mail server couldn't find that address. I have one enterprise account and one App Store account under same team name. My apps run fine so far but I am quite worry if my production apps would suddenly stop working. Attachment is the message from my mail server when I reached out for Apple support team.