To seek Allah's pleasure, as Dua is also a form of worship.
إن الدعاء هو العبادة ثم قرأ: وقال ربكم ادعوني أستجب لكم إن الذين يستكبرون عن عبادتي سيدخلون جهنم داخرين
Supplication is worship. Then he recited: And Your Lord said: Call upon me, I will respond to you. Verily, those who scorn My worship, they will surely enter Hell humiliated. (40:60)
Allah forgives Adam and Eve by teaching them the Dua.
That is because they only disobeyed.
Iblees Was among angels when commanded to prostrate to
Adam. All angels obeyed but Iblees refused claiming he was made of fire and better than Adam who was made of
dust. This is arrogance so he was cursed for all time.
Adam and Eve were forgiven.
The first and worst ...