Hi Aspirant!

In the information broshure HSEE -2021, it is mentioned that , "Candidates belonging to OBC-NCL category must upload online a scanned copy of the OBC-NCL-Undertaking (in the required format). They are required to upload the valid OBC-NCL certificate (issued after April 1, 2021).

Kindly check the issued date of your category certificate. Other than this, I would suggest you to chcek the format of the category certificate. You can check out the required format in the pdf link given below (page 32):

https://hsee.iitm.ac.in/include/pdf/Brochure_HSEE_2021_V1.pdf

Thankyou!