“O My servants who have transgressed against themselves (by sinning), do not despair of Allah’s Mercy. Indeed, Allah forgives all sins. Indeed, it is He who is Oft-Forgiving, Most Merciful.”

وَلَلاَخِرَۃُ خَیرُ لکَ مِنَلاُولاَ

"Indeed what is to come will be better for you than what has gone by."

Saying: “I supplicated and supplicated and I was not responded to.”

For verily, al-Shayṭān casts this in your heart and says: “How much have you supplicated to Allah and what you have sought has not come.”

Then he drives you to despair the mercy of Allah and this is from al-kabāʿir al-ḏunūb (ie: the major sins).

Do not despair from the mercy of Allah even if the response to your duʿāʾ is delayed.