Cognizant — regarding issue of call letter

I have been interviewed on 9th september 2018 at cbit hyderabad. I have received offer letter but i didn't receive any call letter from cognizant (Pega is domain). I got call from one hr in the month of july and she said i will get doj in the month of august. All other students who got interviewed on same day received doj on 13th august, 2019. So, i request you to refer details which are mentioned below and respond as soon as possible. Please intimate my joining date.

Cognizant candidate id : 12486214
Mail id: [protected]@gmail.com
Mobile no: [protected]
[protected]