JANNAH IS NOT a place of any resentment, bitterness, or jealousy. Indeed, one cannot enjoy its bliss with such feelings buried deep in the heart.
You cannot be in Jannah with your believing brothers and have memories that surface of some words or actions they did to you (knowingly or unknowingly) making you resent them. Even if you forgave them in the dunya, these feelings might live hidden in the heart like stains that are never washed away.
So, Allah tells us a beautiful truth that He will remove any such bitterness from the hearts of the believers. There will be no hate, grievance, or ill feeling. Only believers, enjoying the eternal bliss in the presence of their Lord.
Yet another reason to yearn for Jannah.