If the channels are greyed out, and you made those changes a month ago, I'll wager the channels have been removed from your package.
Sky Premiums (Sports & Cinema) have a 30day notice period and if you've lost access using the apps as well, I don't think they're on your account anymore.
You're only going to resolve this by calling I'm afraid. Unfortunately you've also gone beyond the 14day period to cancel whatever change has been made.
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