Can't delete Alex voice from the iOS simulator

I'm working with iOS voices for accessibility reasons. In iOS simulator I've tried to install Alex voice which is one of the most popular English voices. To choose it I downloaded it first. However, after that, the voice looks like something between enabled and disabled.

E.g. for Allison I see that it's not downloaded hence it's not available for me. On the other hand, Samantha is downloaded, so I can navigate further and edit the voice, for example I can delete it. But for Alex I can't neither delete it nor select it to use later.

When I try to press Erase All Content and Settings... for the simulator, sometimes it doesn't change anything, but sometimes it erases Alex voice, but situation returns after downloading this voice. Is there any other way how it Alex can be installed on the simulator?

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