If somebody respectable had told you something was halal when in fact it was haram but it was to late to reverse the damage who’s at fault? Was there anything like this that happened in the Quran? JazzakAllah
Prophet Muhammad (ﷺ) said, "he who called (people) to error, he shall have to carry (the burden) of its sin, like those who committed it, without their sins being diminished in any respect" - Sahih Muslim 2674.
This indicates that the one who calls to misguidance and the one followed in that misguidance both share blame (sin). It applies to someone knowingly calling to misguidance or speaking out of ignorance while he has no right due to lacking knowledge.
In your case,
- If the "respectable" person you mention is just high-profile such as being known for good deeds but not known for scholarly Islamic knowledge then you are at fault because it was wrong of you to blindly follow someone not known for knowledge. He is also at fault for speaking without knowledge and misleading.
- If the "respectable" person you mention is respectable in terms of being known as a Mujtahid/scholar who gives proof and his Ijtihad was just wrong in this case, then he strived to the best of his ability and you followed the general principle of turning to those of knowledge (scholars). No fault on either. But once we get proof showing otherwise, we have to reform our belief/action.
Beyond this, your question is too vague to really give examples or place blame when it comes to worldly damage. My suggestion is going to a scholar and submitting this question with more specifics.