‘Allamah Ibn al-Qayyim (D. 751 رَحمه الله (هـ :

Whoever wrongs you and then approaches you to apologise then humility obligates that you accept their apology whether it be truthful or not and leave their hidden affairs to Allah, the Most High.

This is as Allah’s Messenger (صَلَّ اللَّهُ عَلَيْهِ وَسَلَّمَ) had done with the hypocrites who stayed behind from joining him in battle. When he returned, they came to him giving their excuses and he accepted their excuses and left their hidden affairs to Allah, the Most High.

One of the signs of nobility and humility is that if you see deficiency in their apology then do not address it and do not debate with them. Rather, say, “Perhaps the affair is as you say”, “if something has been decreed then it will occur”, “there is no prevention of what is decreed” and similar statements.

[Madārij al-Sālikīn (3/127)]