Cancellation Payment Trouble GRAD PLUS loan (MOHELA)

Apologies in advanced for the lengthy post. I tried my best to type out my situation.

I have a loan for a total of $45,000 for school that is dispersed to my account every 3 months: Once in Jan, once in march, and once in June. Each 3 months, 10,000 goes towards school and 5000 goes to my account for living expenses.

I have been sending money that I do not use back to MOHELA because according to their website "Payments made within 120 days of a most recent loan disbursement are called Cancellation Payments. These payments are reflected as an amount cancelled from the original disbursed amount for that loan." So, if I send back 5000 dollars back to MOHELA 5 days after the January disbursement date, then that 5000 dollar is subtracted from the principal and the interest accrued is dropped.

My problem

Around 60 days after my June disbursement, I sent back 3000 dollars that I realized would go unused. However, MOHELA counted this payment as a regular old monthly payment that is paid towards the principle and the interest. In other words, this was not counted as a cancellation payment. I have filled out a request for them to count this as a cancellation payment and have talked to numerous people from MOHELA. All have told me it takes 120 business days for this application to be reviewed. However, I have received no updates and my payment still is not reflected as a cancellation payment. I have no idea what to do and could really use some guidance.