Sounds like the freewheel mechanism is bust, likely that the pawls aren't engaging when you pedal. I don't know how mechanically competent you are, but stripping and repairing modern hubs is not for the faint of heart.
@andyp started
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Sounds like the freewheel mechanism is bust, likely that the pawls aren't engaging when you pedal. I don't know how mechanically competent you are, but stripping and repairing modern hubs is not for the faint of heart.