If you can't produce the certificate of EWS then you need to provide a declaration that you don't have the EWS certificate. Such things will be available during the seat acceptance and document verifications procedure. So accordingly you can provide the document as per the required format introduced by the organization.

To know more about the UP NEET Counselling visit the link below:

https://medicine.careers360.com/articles/up-mbbs-counselling

I hope this answer helps. All the very best for your future endeavors!