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Try it from an "Incognito Window" (Chrome) or Private Window (Safari) or whatever the equivalent for your browser. Your cookies or some other content may be the problem.
It seems highly unlikely to me that changing your privacy from public to private is tantamount to relinquishing control over your entire account. You have nothing but time to reinstate it. At least safe from channel being expunged, maybe take some rest?
A sane idea.
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