Is repentance from disbelief completed by merely uttering the Two Testimonies, or is it required to change one's religion in official documents, which might cause the questioner to despair?

Changing one's religion on official documents from Islam to another faith is an act of disbelief (kufr) and apostasy (riddah). Repentance from disbelief is achieved by uttering the two testimonies of faith (Shahadatayn) along with abandoning the act of disbelief. If one continues in disbelief, the two testimonies will not benefit them. A man's continued declaration on his ID card or passport that he is Christian or Jewish is a continuation and persistence in disbelief. However, if he regrets his actions, declares his Islam, utters the two testimonies, and then wishes to change his religion to Islam but is unable to do so, he is excused and absolved from disbelief, as Allah Almighty says: ﴿So fear Allah as much as you are able.﴾ Uttering the two testimonies is repentance from disbelief, provided that one abandons the act of disbelief and does not willingly persist in it.