Girls, who knows? My maternity leave ends today. From tomorrow, I'm on…

Girls, who knows? My maternity leave ends today. From tomorrow, I'm on parental leave. But we haven't registered our child's residency and citizenship yet (we were getting the apartment in our own name for a long time). Without them, I understand that there won't be any payments. Is it possible to receive childcare benefits for previous months if the document of citizenship is later submitted? We are citizens of Russia with the husband.