Why have my prayers not been answered despite my drawing closer to Allah, my constant supplication at all times, my giving of charity, and my faith that He answers the prayer of the supplicant?

It is recommended to persist in supplication with certainty of its answer and to resist the whispers of Satan, and that hastening the answer prevents the acceptance of the supplication. It is not necessary for a person to receive exactly what he asked for, as Allah may replace it with something better for him.