If one can’t find the lender in order to repay a debt, what should one do?

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Check below answers in case you are looking for other related questions:
Is a child obliged to pay off his parent’s debt?
He borrows money from his friend and returns the money to him with a share of the profit

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Related Answers:
Repaying an interest-based loan on behalf of one who has passed away
He is owed money by someone who is going through difficulty, and he has been given some charity money to distribute. Is it permissible for him to take what he is owed from it?
People borrow things and do not return them. What to do?
Is a child obliged to pay off his parent’s debt?
He borrows money from his friend and returns the money to him with a share of the profit

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