BMC Office(L Ward) lack of cooperation

I'm struggling to get the birth certificate of my kid from BMC L-ward. My Wife didn't change her name post marriage and the papers sent from hospital to BMC had only her first name captured. Now the BMC officials are making my life difficult to provide a new supporting document on every visit. The officer looking into this is almost always unavailable Can someone guide me through on how I can escalate this, and get the work done. Whom should I write a complaint for this?