Hello Priya,

If by OBC certificate you mean OBC Non-Creamy Layer certificate then you will need to apply afresh and obtain a new certificate because the validity of an OBC NCL Certificate is treated as 1 year.

Since your OBC NCL certificate was obtained before 1 year, it is better to apply for a new OBC NCL now as it is a time taking process and may hurt your chances if you leave it for the last minute for admission in the University of Delhi as during document verification you will need to produce valid certificate.

Hope this answers your query, feel free to ask for more info.