Harmony vocals


I’m trying to generate harmony vocals in Cubase pro 9. However, when I select vocal segment in the project window and open the “Audio” menu the command “Generate Harmony Voices” is greyed out. Does anybody know the reason that this is happening. Incidentally, I have recently installed the Cubase 9 update and I’m sure that prior to this the option listed in the “Audio” menu was “Create Harmony Vocals” and this worked fine. Any help would be fully appreciated

please help

I did not find the right solution from the internet.

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