In my case, I found that CFBundleVersion should not contain leading zeros after a period.
15.06011812 should be 15.6011812
As soon as we fix this, the settings are completed in the TestFlight user interface (then a switch for the watch application appeared and appeared).
After that, I found this answer in search of a โtest runโ.
TestFlight believes that it never completed the installation, because the CFBundleVersion in the installed Info.plist application contains a leading zero, which makes it an older version of the application. When I exited TestFlight and restarted, he thought an update was available.
Until I tried to install the Watch app, it was just an annoyance in the user interface, but then it prevented me from seeing the switch for installing the Watch app.
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