Hi,
Your application may have expired due to not registering or paying the fees. You can try for a fresh application form but try to do it as soon as possible because today is the last day for registering for the April session for JEE. The link for applying will be available on the official site.
You can refer to this link for detailed steps: https://engineering.careers360.com/articles/jee-main-application-form
I hope this helped you.
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