In Islam if a person says something with a particular intention but then the other person understands it differently, what should be done if the listener got in big trouble and lost a huge sum of money because of this misunderstanding?

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

A person is not religiously held accountable for the misunderstanding of the listener to his speech. Therefore, the listener is responsible for his misunderstanding, but if the speaker helps him with the amount of money that he had lost, then this is better, but he is not obliged to do so.

Moreover, you have to know that the question needs to be clarified, so you can refer to some scholars in your country and expose the issue clearly to them, or you may send us a more detailed question, and we will answer it. Because, we do not know the dialogue that took place between these two people nor the circumstances in which it took place.

Allah knows best.