What verses and hadiths urge setting aside disputes, to help someone who is trying to restore his relationship with a relative after a dispute that lasted three years?

Corruption of mutual relations weakens faith and removes it, due to Allah's saying: "So fear Allah and amend that which is between you," and the Prophet’s (peace be upon him) saying: "Rectifying mutual relations is better than the rank of fasting, prayer, and charity, for indeed, the corruption of mutual relations is the cutter." To increase love among Muslims, the following are recommended: Giving gifts, for he (peace be upon him) said: "Give gifts, and you will love each other." Smiling and showing cheerfulness upon meeting, for he (peace be upon him) said: "Your smile in the face of your brother is charity for you." Choosing the best of words and avoiding what angers others, for Allah Almighty said: "and speak to people good words." Turning one's face towards the person while speaking, for he (peace be upon him) said: "Do not belittle any good deed, even meeting your brother with a cheerful face." Listening well, not interrupting, and showing respect for his opinion. Calling him by the names he likes most, and making space for him in gatherings.