Assalaam alaikum, If a person was kind and generous to people, and helped them in their bad times, and those same people treat him badly in a rude way and in an ungreatful way, disgracing him.. When the first one is going through bad times. If that person reminds them by saying is this the way you treat a person who was kind to you. Does this come under the prohibition of reminding people of favours?? when is it permissible and when is it haraam?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

Reminding those people of what you had done to them is a kind of mentioning one’s favors and in principle this is forbidden. But if there is a sound purpose for doing so, then there is nothing wrong with it.

Ibn Hazm said in this regard: “It is not permissible for anyone to remind others of his favors upon them unless one has done much goodness to others while he is unjustly treated by them; in which case he may numerate his favors upon them.”

He (Ibn Hazm) gave as evidence the story of the Prophet when he divided the war spoils in the battle of Hunayn and the Ansaar were not happy with the division; so the Prophet addressed them saying: “O people of Ansaar, did I not find you erring and Allaah guided you aright through me, and (in the state of) being destitute and Allaah made you free from want through me, and in a state of disunity and Allaah united you through me?” The Ansaar replied: “Allaah and His Messenger are most benevolent.” He (again) said: “Why do you not answer me?” They said: “Allaah and His Messenger are the most benevolent.” He said: “If you wish you should say so and so, and the event should take such and such course, and (in this connection) he made a mention of so many things.”

Allaah Knows best.