I am really struggling with registering my app in App Store Connect. I find the system to be complicated an unhelpful. I have two issues with my app. I can see the builds that I have uploaded from Xcode when I select "Add Build" from the "IOS App" page. But for some reason, I cannot select a build - as there is no error message or guide as to why I can't select the build, I am asking here. I have created a Subscription Group for my app in MONETIZATION -> Subscriptions. I have created the Reference Name and Product-Id. It has been saved. App Store Connect tells me there is Missing Metadata but once more gives me no clue as to what is missing and how to correct it. As far as I can see I have completed everything needed for the Subscription Group/Product. I would like to add a Trial Period to my subscription but I cannot see anywhere to do this. The UI for Apps Store Connect is terrible - I would expect errors to be flagged and some suggestions given as to why the error exists - nothing! Is there a helpful (and understandable) guide I could use for setting up the App and any suggestions from the forum as to what I need to do to get my app ready for review and testing in Test Flight. Thanks!

I have had an app on the apps store for about 4 years. The app uses an API to retrieve some data and displays/manipulates it. The app works for the vast majority of users however, for around 0.01% of users, the first time they open the app after downloading it, the API fails and reports that it cannot retrieve data (it exits elegantly but does not crash). They cannot get the app to work and I have to issue a refund. I cannot repeat the error on simulator or on my test iPhone (13). There is no consistency on IOS or phone model reported. I am guessing that there is some form of configuration that cause the app to fail to retrieve the data. I don't even know where to start to identify the problem. Can anyone point me to some documentation or provide advice as to how I can capture, analyse and fix these rare failures. Thanks