He's always convinced that his opponents will knuckle under to his overwhelming force (physical, economic, personality, etc.) I get the impression that it has worked out for him in the past. It certainly wins elections. (He would surely have won in 2020 were it not for a once-in-a-lifetime emergency.)
So Iran does want a ceasefire. But Trump wants it more, because he knows how much damage he's doing to his reputation.