The birth certificate of Beijing child's father does not show the electronic signature, so it can be reissued. For babies born in the hospital, regardless of whether the mother is married or not, the hospital has to apply for the baby's birth certificate, but the father information is blank. In this case, you can bring the discharge record of being hospitalized at that time. If you don't have an invoice, bring your ID card, check your birth record and ask for a replacement. If the hospital does not do it, it is recommended to report it to the health department.