I handled it for my daughter because 1) she asked me to (she’d just turned 17, really had no idea how the money would all come together) and 2) she was in school during the hours the FA/Admissions offices were open and cell coverage at her school was pretty bad (on purpose as they didn’t want kids on their phones).
The school didn’t mind at all. The request for more merit was really a request to see if the amount we got was correct. It wasn’t as they’d used the wrong test score so fixing it was easy.