Is it necessary to consult more than one religious authority when seeking a fatwa to ensure agreement, or is it sufficient to consult only one?

If the responsible authority or the scholar being asked for a fatwa is qualified to issue it, then there is no need to repeat the question. The questioner is permitted to act upon their fatwa without consulting others, because they have fulfilled what they were commanded to do, which is to ask, as Allah Almighty says: "So ask the people of the message if you do not know." (Quran 16:43). Repeating the question to more than one scholar may lead the questioner into confusion and distress due to the differing fatwas of scholars.