For the above problem, I received a suggestion.

I was told that the only solution for this is uploading a letter with your request for the change of the clause code with your own study certificate in place of your parents study certificate.

Hey I am facing the same problem. How did you get it solved? Did you face any problem. Please answer

Hi,

   For this, you will have to contat Kanataka Examinations Authority (KEA). I am providing the contact details below.

Phone : 080-23460460 ( 10.30 am - 4.30 pm on working days)

Email : keauthority-ka@nic.in

KEA website : https://cetonline.karnataka.gov.in/kea/indexnew.aspx

Hope this helps you. All the best.