National insurance number

Hello,
I am writing to you regarding an issue I encountered while providing my National Insurance number for my first student finance application, for the undergraduate programme. Upon noticing the requirement for this number, I made a request on 27th March 2024. Following my request, I received confirmation from them, informing me that they had duly noted my request and that I should wait. After three weeks, I finally received their letter on 14th April 2024, containing my National Insurance number. I then entered it on the Student Finance website as per the instructions.
However, I am facing an issue as their system seems to have already recorded this number, which seems peculiar to me. They have subsequently asked me to upload proof on the Student Finance website. However, they have also specified not to upload any original documents and that it is necessary to send the proof by mail, as they need to see the original documents. However, the only original proof I have of my National Insurance number is the letter received on 14th April.
I am therefore wondering how to proceed in this situation. Is it possible to upload this letter on the website so that they have proof of my National Insurance number?
Thank you for your assistance.
Yours sincerely,
Marli

Hi Marli, are you applying for the first time for 24/25 academic year?
Thanks,
Claire

Hi there. You are able to use your letter from the Department of Work and Pensions as proof of your National Insurance Number. It doesn't need to be the original letter, but we would ask you to post this to ensure it is picked up by the correct team who deal with this.
Please send it with your student finance customer reference number.
All evidence should be sent to:
Student Finance England
Team 6
Assessing Services
The Student Loans Company
11 Carnegie Road
Hillington
Glasgow
G52 4JT
Thanks, Leah.