Activation issue

Hello, I bought an education license that I used on two old macs. I am using a new one, (the other computers were sold in parts). I cannot activate marginnote 3 on my new computer because I can’t find my activation number. I´ve contacted the service@marginnote email, but no response. All my work is depending on marginnote working, so I can’t work, please help. I payed through fastspring.