Hi Preeti,

According to the eligibility criteria of DU JAT 2017, candidates who had appeared for an improvement exam could not apply for the exam but could apply the next year. there are chances that the eligibility criteria would remain the same this year as well. 
You could look into the eligibility criteria for this years dmissions to find out the same.

for further information about last years eligibility criteria you can refer to the following link : https://bschool.careers360.com/articles/du-jat-eligibility-criteria

And to know more about this years Eligibility criteria you can stay tuned to the website page.

All the Best