The longest verse in the book is about writing debts down
The longest verse in the Qur'an is about debt, and its instruction is to write it down. Precisely, with witnesses, with the amount and the term stated, and it explicitly tells people not to be too embarrassed to record it whether it is small or large.
That is worth sitting with if some part of you feels that looking at the actual figure is unspiritual pedantry, or that a person with real trust would not need to check. The Qur'an's own treatment of debt is documentation.
Alongside that, two supplications, and both are worth having as long as they sit beside the action rather than in place of it.
The Prophet, peace be upon him, sought refuge from worry and grief, from incapacity and laziness, from cowardice and miserliness, from being heavily in debt and from being overpowered by other men. Worry and debt named in the same breath, as things it is reasonable to ask to be protected from. Note the reference, because the one that circulates for this is often wrong. It is Sahih al-Bukhari 6369. Bukhari 2893 is a different report about the Khaybar expedition.
And the supplication Ali taught the man who came to him asking for help. O Allah, suffice me with what You have made lawful against what You have forbidden, and make me independent by Your bounty of everyone besides You. Look at the setting of that one. A man in difficulty came to another human being and asked for help, and he was given both the words and the help. Not one instead of the other.
Qur’an and Sunnah
يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوٓاْ إِذَا تَدَايَنتُم بِدَيۡنٍ إِلَىٰٓ أَجَلࣲ مُّسَمࣰّ ى فَٱكۡتُبُوهُۚ وَلۡيَكۡتُب بَّيۡنَكُمۡ كَاتِبُۢ بِٱلۡعَدۡلِۚ وَلَا يَأۡبَ كَاتِبٌ أَن يَكۡتُبَ كَمَا عَلَّمَهُ ٱللَّهُۚ فَلۡيَكۡتُبۡ وَلۡيُمۡلِلِ ٱلَّذِي عَلَيۡهِ ٱلۡحَقُّ وَلۡيَتَّقِ ٱللَّهَ رَبَّهُۥ وَلَا يَبۡخَسۡ مِنۡهُ شَيۡـࣰٔ اۚ فَإِن كَانَ ٱلَّذِي عَلَيۡهِ ٱلۡحَقُّ سَفِيهًا أَوۡ ضَعِيفًا أَوۡ لَا يَسۡتَطِيعُ أَن يُمِلَّ هُوَ فَلۡيُمۡلِلۡ وَلِيُّهُۥ بِٱلۡعَدۡلِۚ وَٱسۡتَشۡهِدُواْ شَهِيدَيۡنِ مِن رِّجَالِكُمۡۖ فَإِن لَّمۡ يَكُونَا رَجُلَيۡنِ فَرَجُلࣱ وَٱمۡرَأَتَانِ مِمَّن تَرۡضَوۡنَ مِنَ ٱلشُّهَدَآءِ أَن تَضِلَّ إِحۡدَىٰهُمَا فَتُذَكِّرَ إِحۡدَىٰهُمَا ٱلۡأُخۡرَىٰۚ وَلَا يَأۡبَ ٱلشُّهَدَآءُ إِذَا مَا دُعُواْۚ وَلَا تَسۡـَٔمُوٓاْ أَن تَكۡتُبُوهُ صَغِيرًا أَوۡ كَبِيرًا إِلَىٰٓ أَجَلِهِۦۚ ذَٰلِكُمۡ أَقۡسَطُ عِندَ ٱللَّهِ وَأَقۡوَمُ لِلشَّهَٰدَةِ وَأَدۡنَىٰٓ أَلَّا تَرۡتَابُوٓاْ إِلَّآ أَن تَكُونَ تِجَٰرَةً حَاضِرَةࣰ تُدِيرُونَهَا بَيۡنَكُمۡ فَلَيۡسَ عَلَيۡكُمۡ جُنَاحٌ أَلَّا تَكۡتُبُوهَاۗ وَأَشۡهِدُوٓاْ إِذَا تَبَايَعۡتُمۡۚ وَلَا يُضَآرَّ كَاتِبࣱ وَلَا شَهِيدࣱۚ وَإِن تَفۡعَلُواْ فَإِنَّهُۥ فُسُوقُۢ بِكُمۡۗ وَٱتَّقُواْ ٱللَّهَۖ وَيُعَلِّمُكُمُ ٱللَّهُۗ وَٱللَّهُ بِكُلِّ شَيۡءٍ عَلِيمࣱ
You who believe, when you contract a debt for a stated term, put it down in writing: have a scribe write it down justly between you. No scribe should refuse to write: let him write as God has taught him, let the debtor dictate, and let him fear God, his Lord, and not diminish [the debt] at all. If the debtor is feeble-minded, weak, or unable to dictate, then let his guardian dictate justly. Call in two men as witnesses. If two men are not there, then call one man and two women out of those you approve as witnesses, so that if one of the two women should forget the other can remind her. Let the witnesses not refuse when they are summoned. Do not disdain to write the debt down, be it small or large, along with the time it falls due: this way is more equitable in God’s eyes, more reliable as testimony, and more likely to prevent doubts arising between you. But if the merchandise is there and you hand it over, there is no blame on you if you do not write it down. Have witnesses present whenever you trade with one another, and let no harm be done to either scribe or witness, for if you did cause them harm, it would be a crime on your part. Be mindful of God, and He will teach you: He has full knowledge of everything
Qur’an 2:282
Narrated Anas bin Malik:The Prophet (ﷺ) used to say, "O Allah! I seek refuge with You from worry and grief, from incapacity and laziness, from cowardice and miserliness, from being heavily in debt and from being overpowered by (other) men." (See Hadith No)
Sahih al-Bukhari 6369graded sound, sahihaynfull report
Ali [may Allah be pleased with him] narrated:that a Mukatib came to him and said: “Indeed I am not capable of my Kitabah so aid me.” He said: “Should I not teach you words that the Messenger of Allah (ﷺ) taught me? If you had a debt upon you similar to the mountain of Sir, Allah would fulfill it for you. He said: ‘Say: O Allah, suffice me with Your lawful against Your prohibited, and make me independent of all those besides You (Allāhummakfinī biḥalālika `an ḥarāmika, wa aghninī bi faḍlika `amman siwāka).’”
Jami' at-Tirmidhi 3563graded sound, albanifull report
Translation: M.A.S. Abdel Haleem, The Qur'an, Oxford University Press, 2004.