DV Case Still.going On

I will be filing interim maintenance in next hearing date. meanwhile my husband did not give me my son birth certificate who was born aboard. last year even when police asked he skipped saying he doesn't have but he had 6 copies where we both went and took in USA. Now can I ask him in email to send me birth certificate. is it allowed to contact husband when case is going on. also my husband is not in contact since 2 years. please help.