There was pin-drop silence in the assembly, No one knows what to say about this condition of Karna. Wise in the group of people understand this is the best thing Karna can ask for but they did not think it is even possible.
Rishi Durvasa not giving curses when being angry is the same as expecting the sun to rise from the west, Expecting water will give up its nature of being cool, Expecting fire to not burn things.
This is just illogical. There might come a day when all three things said up can happen but Durvasa not giving a curse being angry will never going to happen, The one who thinks it will happen will be the way about to be cursed.
In this case that person is Karna.
"*Ahem* Insolence!! Putra I thought you are good but you are very disappointed. Asking a great Rishi like Durvasa this? You should have thought this is your honour to be allowed to be the first student of Rishi Durvasa.