You can't (without simply brute forcing) unhash a hashed value, that's the entire point.

If the hashes were salted (adding a randomized value to the hash function) then stolen password hashes are essentially useless (in terms of guessing the real password) unless you got a really weak password (something below a quadrillion combinations). Unless someone really wants your account hacked for some reason and is ready to pay some cash for it, then you need a few orders of magnitude more.

If they were not salted then that is another matter, much easier to get to the real password (especially if weak) then.