Hello. Make sure that you have filled your application accurately and re-login into your account at the Jamia Milia Islamia website. Check if the registration slip generation option is showing anywhere, if not then immediately email or call the University. Click on the link provided below to get the contact details of Jamia Milia Islamia University Admissions Helpline -

https://www.jmi.ac.in/studyatjamia/jamiafaq/5