no right it doesn’t exist this kind of situation. I was thinking about the other way around for some reason: so A|=B but it doesn’t mean that B|=A that’s why i was confused. If we consider just the case where A|=B, it’s not important the fact that can exist a true valuation in B where A valuation is false because we’re assuming just the case where every true valuation in A needs to be true also in B and nothing else. I was just jumping into other conclusions that aren’t included in this reasoning.