Is it permissible to seek the help of a brother in managing affairs while abroad, and does this contradict the Hadith: "If you seek help, seek help from Allah"? And is it better not to seek assistance and to be hard on oneself? And will a person be rewarded if he intends, by seeking help from his brother, to bring joy to him?

Islam encourages preserving one's dignity, and asking for financial help may be unlawful if there is no urgent need. If there is a need, there is no harm in seeking assistance from a person if they are able to provide it. Refraining from asking is preferable to preserve one's dignity, unless there is a need, especially if the person asked is known for their righteousness and generosity. If you intend to bring joy to them, you will be rewarded.