Dear Rabbi Simon,
I just made havdalah but on 0.5 % volume beer. It is also advertised as alcohol free beer. Is this valid? Do I need to make havdalah again?
I am not sure if beer-drinkers consider the alcohol-free version to be completely authentic, however the distinction can be overlooked WRT חמר מדינה status. So you do not need to repeat havdalah.
Rabbi Rashi Simon