Hi

I hope you selected EWS category in the form and filled the self declaration form in the prescribed format for candidates who don't have a valid certificate  and upload it in lieu of EWS certificate before submitting the final form as it cannot be uploaded later. According to the recent update from JEE advanced officials you can upload the valid certificate ( dated on or after April 2021) at the time of reporting to Josaa.

"Notice to candidates:

Candidates who are not able to upload a valid category certificate (for ALL categories) during registration, can upload a self-declaration in lieu of the same, and must upload the valid certificate at the time of reporting during JoSAA.

If you haven't uploaded self declaration and have selected your category in the form then you get a clarification on this issue from the helpline no of JEE advanced. They have the final say in this matter.

https://jeeadv.ac.in/contact.php

Hope this helps.