Hi,
the order number isn’t that important either, and if you’re asked for it, just put “00000000” … (there were many topics mentioning this before the community was overhauled).
On the other hand, David says that e-mail is the best solution, but I generally recommend CHAT if it’s available when you make the request (if not, try again later)… It’s easier to interact with support in real time, and you can also send attachments as proof.