Caste Dynamics in Uttar Pradesh

Hi guys, hope you are all doing fine. Today, I was thinking about my surname/caste, and I realized that people with the same surname can belong to different castes and vice versa. For example, I write Sharma as my surname, and so do my mom and dad. However, in my ancestral village, all my family members write Vishwakarma/Panchal as their surname, and we fall under the OBC category. I asked my grandmother about this, and she told me that we are (Badhai) descendants of Lord Vishwakarma, the god of creation and craftsmanship. To my surprise, she mentioned that we are considered (Jangid Brahmin), a group ranked lower than regular Brahmins but higher than other castes in the social hierarchy. When I asked her why my father uses Sharma as his surname, she said that when he moved to the city, he changed it to Sharma. Here in UP, specifically in Jhansi, the surname Sharma is associated with Brahmins/Pandits, so all my friends call me "Panditji" 😂. But in western UP and Bihar, the surname Sharma is considered a common surname and isn’t necessarily linked to Brahmins or Pandits. An incident happened to me some time ago during an SSC exam. The guy sitting next to me (I think he was Mishra and much older than me) asked for my name before the exam. When I told him my name, he asked, "Panditji hain?" I was in a dilemma about how to respond. However, he saw "OBC" written on my admit card and laughed it off. That whole day, I kept thinking about whether he was mocking me or just dismissing the matter. What still bothers me is why my father chose Sharma as our surname when we also have "OBC" on all our documents. I’ve lived my whole life with this surname, and all my official documents reflect it. My question is: can I give up my caste certificate as an OBC on all my documents? I feel this would make more sense than changing my surname. What is the legal process for this? Any advice or suggestions are most welcome.