Cognizant Technology Solutions — I haven't received the offer letter yet

Address: Chennai, Tamil Nadu, 500088

Hi, i have been interviewed for the role of informatica developer for chennai location. After telephonic interview, i have been requested to attend face to face interview at hyderabad location on 21st nov 2018. The hr told i was selected and the package discussion was completed on 24th of november 2018 and he said he will roll out the offer. Its been nearly 40 days and no response from them. I have attended this through a consulting firm named careernet.