I had the same problem and literally tried all the answers above! I even tried to introduce a new assembly, thinking that this could be a problem. But still showed the same error.
I contacted Apple Developer support several times and, in the end, received a response from them.

So let's go. That was my problem. And I just could not understand it without their email. I was practically thinking about refusing to host the application on the iOS App Store.
Sankalp Singha Sep 24 '19 at 15:18 2019-09-24 15:18
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