Caste certificate but Father Leaving certificate not mention sub Caste

My name is Sneha . My We are south Indian (Telugu ) and my caste is Hindu Padmanshali. I want to make caste certificate. But in My father leaving certificate only Hindu is written and Padmashali as Sub caste is not written. My grand parents are expired and my father has one sister ( My Bua). My mother's Leaving certificate has Mentioned Padmashali as Sub -caste. As of now my and my fathers blood relatives has no Caste certificates. Can I get Caste certificate based on mothers leaving certificate. Also can i make affidavit to get caste certificate ? PLEASE HELP ME. I want to do job in govt office and so that i need it please.