Is it permissible for a Muslim to ask God to afflict him with a specific matter in exchange for achieving another important goal, and is this considered bartering in supplication or covetousness?

The Prophet, peace and blessings be upon him, forbade supplicating against oneself, one's children, one's servants, and one's wealth, as he said: "Do not supplicate against yourselves, and do not supplicate against your children, and do not supplicate against your servants, and do not supplicate against your wealth. Do not coincide with a moment from Allah in which He is asked for a bounty and it is granted to you." And he said: "Do not supplicate against yourselves except for good, for indeed the angels say 'Ameen' to what you say." Scholars have interpreted this prohibition as one of disfavor (karahah). It is more befitting for the supplicant to be resolute in their request, to implore Allah earnestly in supplication, to have a good opinion of Him, and to be certain of a response, and not to say: "O Allah, forgive me if You will." For indeed, nothing that Allah bestows is too great for Him. And he should avoid supplicating against himself and take the means that lead to the acceptance of supplication, such as consuming lawful food, persistent supplication, and seeking out times when supplications are likely to be answered.