Cognizant — I haven't received my offer letter yet

Address: H.No 6-3-1100/4/2, somajiguda, Hyderabad, Andhra Pradesh, 500082

Hello. I'm Geethika. I got selected the CTS drive for the role of PAT on 23rd march 2019 at CTS Hyderabad. They have mailed our college T & P department about the selected students on 25th march 2019, but till now i.e 19th june 2019 I haven't received any mail from the company. Approximately more how much time will it take to receive my offer letter?