Schedule tribe caste certificate

I am a student from vishakapatnam. I have qualified for my jee advanced exam. I belong to the caste ST(KONDA KAAPU). So to get into admission process I should submit my caste certificate. We have the following documents My father's ST certificate-1992 My grandfather ST certificate-1966 n 1985 Both got their certificate from telangana. I am a native of ANDHRA PRADESH from my birth. From my childhood all the certificates have been mentioned the caste to be ST KONDA KAAPU. And I have never applied for the certificate till this year. My late grandfather is a government employee with a service of 30 yrs And my father is a private employee. We have applied once in the month of feb and it got rejected mentioning that sufficient document not provided And when the second time we applied the certificate it was again rejected saying that THEY HAVE NO AUTHORITY TO ISSUE THIS CASTE but according to THE SCHEDULE CASTE AND SCHEDULE TRIBE AMENDMENT ACT 2002 in non schedule areas the authority to issue this certificate lies with the RDO/SUB COLLECTOR/ASST COLLECTOR but our certificate is rejected by the MRO and is not being processed to the RDO and no enquiry was done before the rejection As of my father's knowledge the native of their forefathers is Srikakulam and they have migrated that place at 1920s. So we have no known relatives at that place because since last 100 years they were living out of the place and have migrated to telangana and borders of orrisa. Please suggest me what to do with this case.