Does continuous supplication alter Allah's decree in repelling evil from a person, and does repentance repel this evil more than supplication?

Supplication (Du'a) can repel destiny and ward off evil, by Allah's permission. Repentance is among the greatest means of lifting affliction, for no affliction descends except due to a sin, and none is lifted except through repentance. Moreover, repentance is a form of piety towards Allah, and "whoever fears Allah - He will make for him a way out and will provide for him from where he does not expect."

The people of Jonah are an example of this. When they believed after witnessing the signs of torment and cried out to Allah, Allah removed from them the torment of disgrace in the worldly life and granted them enjoyment for a period.

There is no evidence to suggest that repentance is superior to supplication in repelling affliction; both are a means to good.