Making a large payment or additional payment does not automatically change your monthly payment. For a fixed-rate loan, you will continue to owe the same amount the following month unless you request a re-amortization, which may lower your monthly payment.
For a variable-rate loan, you will also owe the same amount the following month unless you either (1) request a re-amortization, or (2) the LIBOR or SOFR rate changes and your loan re-amortizes due to a change in your interest rate.
If you have made additional payments to your loan, MOHELA and SoFi may be able to re-amortize your loan, which may reduce your monthly payment. You may initiate this request by calling MOHELA directly at 877-292-7470. If your loan is serviced by SoFi, you may initiate this request by callling SoFi at 855-456-7634.