Weird things....
Now after saving, suddenly even the subcategory "Vini rossi" has disappear.
Than I go - from the top menu - to category "vini rossi".
Than back to shop home page.
Sub Categories for redwine has appeared again, except for white wine Crisoperla.
Please not that I have cancelled my cache more and more time.
So it is not even a problem of cache.
I am doing websites since 1998 and with Joomla since 2009, I can understand everything and maybe I can go wrong with some settings, but this is really strange.
Beyond any reasonable doubt I am afraid it's just a bug of VM.