Accidentally skipped questions on census, what can I do?

I skipped the last purple pages on the census, filled in most of my personal data but there’s some gaps, what can I do? I didn’t realise you can’t even go back and edit it or anything. Apparently I’ll get fined $300 a day I can’t afford that. Could someone give some genuine advices please should I contact someone or will it be okay to leave it ?