Bc to sc

Dear All,

I am Daniel. I live in Chennai. My ancestors are from Andhra Pradesh.

I belong to Adhi Andhra caste, it is one of the Scheduled Caste. In Tamil Nadu all Christians are recognized under BC.

My community certificate indicates BC but in sub caste it is mentioned as Adhi Andhra. 

I would like to change the community certificate from BC to SC. 

Please let me know the possibility to make this transition. 

Thanks and Regards

Daniel