Cognizant Technology Solutions — offer letter not received its been 30 days

Address:

Manyata tech park, Bangalore, Karnataka

I have attended an interview at cts bangalore (Manyata tech park) on june 1st 2019 and cleared all the rounds. At the end hr informed me that i will receive my a confirmation mail in a week and offer letter in a month but i haven't received yet. Meanwhile i received an email from cts talent acquisition that i got shortlisted but no offer letter has received till now. Please tell them to send my offer letter and joining as soon as possible.