Cognizant — Offer letter not received -.net developer role

This is uday saikiran vurrinkala, regarding below mail. my HR discussion happened on 18th august 2021 n sent docs on 19th august almost a month back .i have been waiting for this offer since a month, i even rejected other 2 offers which was offered to me as am very much interested to join CTS. In HR discussion HR was mentioned budget is 10 lakhs, so I accepted the same..but couple of days back I got mail saying unable to match up to ur expectations.I felt very bad even after continues follow up with HR and HR mentioned I will get offer for sure .now your saying it’s not matching expectations means I am not able to take it.Could you please let me know atleast where exactly wrong