What is the legitimate stance, and what should I do if I have been lenient in taking money from some young men as a loan or a gift and forgot to return it, and I am unable to repay the debt due to difficulty communicating with them? And is it obligatory to inquire about the debt if I do not remember it? And is one absolved of responsibility if the person waives their right due to difficulty in communication?

If the money paid by the young men was out of courtesy and generosity, not as a loan, then it is not obligatory to return it, and the default is the innocence of one's liability. However, if it was a loan from a specific young man, then it must be returned to him. It is not a condition to contact him directly; rather, it is sufficient to authorize someone else to return it by any means that does not cause embarrassment or harm. Nor is it required to inform him that you are the sender. Al-Juwayni said: "Everything whose obligation is ambiguous, the default is the innocence of one's liability regarding it."