Is it obligatory to change the name in official documents to the real father's name only upon marriage, or should it be changed in all professional, academic, and other transactions, and what is the importance of being attributed to one's real fathers in Islam?

There is a severe warning and threat for anyone who affiliates himself with someone other than his father, while knowing that he is doing so. The Prophet, peace and blessings be upon him, said: "No man claims to be the son of other than his father, while knowing it, except that he has committed disbelief." Imam Al-Nawawi explained the phrase "except that he has committed disbelief" with two interpretations: either it refers to one who deems it permissible to do so, or it refers to disbelief in blessings, kindness, the right of Allah, and the right of his father. Allah Almighty says: {Call them by their fathers' names; it is more just in the sight of Allah.} (Quran 33:5). It is obligatory for anyone who has affiliated himself with someone other than his father to correct his lineage by attributing himself to his true father in all his dealings.