Can't save version when build is attached in ASC

I've got an app. I've gone to AppStore Connect and filled in everything I can think of (screenshots, encryption status, privacy nutrition label, description, categories, everything), and I can save. I want to actually get the thing submitted at least so beta testers can get it, and when I attach a build, the save button just goes to red bordered with an exclamation point in it.

I don't see any error messages anywhere or underlined things. I've asked ChatGPT and Claude for guidance and tried all the things the mentioned, and I have had no luck.

I've also tried three different builds -- one of them is about a month old at this point. I've tried contacting support for the last month with no luck.

How can I figure out what's wrong so I can fix it?

Can't save version when build is attached in ASC
 
 
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