Under what circumstances may a person receive payment for a loan if he did not, for whatever reason, write a Prozbul before the end of a Shemita year? The end of the Shemita year automatically cancels all outstanding debts, unless a person writes a special Prozbul document which allows him to collect his loans. The question thus arises, what should one do if he realizes after Rosh Hashanah that he neglected to write a Prozbul?
Halacha forbids a person in this case from approaching the borrower to demand repayment of the loan ("Lo Yigos" – Debarim 15:2). Moreover, if the debtor approaches the lender and volunteers to repay the loan, the lender must verbally declare, "Meshamet Ani," meaning, "I cancel the loan." The Torah refers to this obligation as "Debar Ha’shemita" (literally, "the word of Shemita"), indicating that the cancellation of the debt must be proclaimed verbally.
If, however, the borrower nevertheless offers to pay even after the lender announced the debt’s cancellation, the lender may accept the money, provided that it is made clear that he accepts the money as a gift. If the lender expresses his offer by saying he wishes to "repay the loan," the lender must clarify that he accepts the money only as a gift, rather than as repayment for the loan. Once both sides agree that the money is paid only as a gift, the borrower may then pay the sum in question to the lender.
In fact, the Sages encourage borrowers to voluntarily pay borrowed sums after the end of the Shemita year. The Talmud says about such people, "Ru’ah Hachamim Noha Hemanu" – "The Sages are pleased with him." The Sages do not wish for lenders to lose their money, and it is therefore commendable for borrowers to offer to pay the cancelled debt in the form of a gift in a case where a Prozbul was not written.
Summary: If a lender did not write a Prozbul document before the end of the Shemita year, he may not demand payment from the borrower, and if the borrower approaches him to pay, he must verbally declare that the debt is cancelled. If the borrower still wishes to repay the loan – which he is in fact encouraged to do – the lender may accept the money provided that both parties agree that the money is given as a gift, and not as repayment for the loan.