Problem
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Let $P(A) = 0,4$ , $P(B) = 0.6$, $P(A \cup B) = 0.86$.

Now solve $P(A \cap B)$

 Attempt to solve
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I know that when $A$ and $B$ are independent events, then

$$ P(A \cap B) = P(A)P(B) = 0.4 \cdot 0.6 = 0.24. $$

I also know that if $A$ and $B$ are independent then

$$ P(A \cup B) = P(A) + P(B) - P(A \cap B). $$

Now I could use the previous equality to solve for $P(A \cap B)$ which results in

$$ P(A \cap B) = P(A) + P(B) - P(A \cup B) = 0.4 + 0.6 - 0.86 = 0.14 $$

Now I don't really understand why I have two different results?