I reallllllly need help... I missed the actual PSAT test today?

I've been sick for a good few days, and I took medicine last night forgetting that I had the PSAT test the next morning, and ended up oversleeping, and waking up an hour late of the test. My parents don't, well I guess you can say...they don't do anything for me when it comes to school things whatsoever. So I can't even depend on them to sign papers, let alone wake me up for the test. I'm a Junior, so this is a big deal. I went on the website and it says to "write to NMSC as soon as possible but no later than March 1 following the PSAT/NMSQT administration that was missed. Your letter must be postmarked on or before March 1 for your request to be considered." - from the website. Now my question is, since it's a letter, WHO DO I ADDRESS IT TO?! like Dear _______________, WHAT?! :/ Please help. I honestly can't do anything else but this. Taking the test next year would be pointless.