Is it permissible for the Mufti to retract his fatwa concerning divorce if the husband presents new evidence that he had not mentioned previously due to his ignorance, such such as claiming that he did not utter the words of divorce, but rather that it was based on his wife's statement?

The Mufti (definition) must retract his fatwa (definition) if it becomes clear to him that the premises upon which the first fatwa was based are incorrect. The new fatwa is then considered a ruling on a new question. The Mufti should not rush to issue a fatwa, but rather should complete the information related to the question, as Ayyub al-Sakhtiyani did. A fatwa is merely an informing of the legal ruling and is not binding, unlike a judicial verdict which is binding. A judge is not permitted to retract his judgment except in specific cases.