Cognizant review: asking information

I am Chinni Juluru.I got the offer letter in February and the students in some colleges who got offer letter in February got the call letter and date of joining on June 14 and we have not received them.so please send me the information regarding this issue as we are very much eager about it or at least send us the information when we will receive our call letter. Please send me the information as early as possible. And we have completed our challenges like L0 and L1.so please respond about this issue as soon as possible.