I’m also having the same issue of the unresponsive left side of the screen, on iPhone XS after iOS 15 update. Resetting all settings seemed to fix it, though - but only temporarily. The issue came back, but randomly resolved again and now has come back once again.
From all these replies with the same problem, it definitely seems like it’s something to do with the iOS 15 update. Here’s hoping there’s a bug fixes update that sorts this out soon
khai02
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