HCL Technologies — Submitted all documents but didn't receive Offer letter

Dear HCL,

I Got an Email on Oct 11th as your resume is shortlisted from HCL, and later, I received an Assessment link for the position: Of Associate Consultant on 26th Nov 2021

I have attempted the test, and later I got an email that you are a good fit for the role, and we wish to move ahead for further discussion then. I have submitted all my documents
and HR discussion happened on the same day i.e., 7th Dec 2021
I was told that Hyderabad is the work location earlier, but upon # discussing with HR, Hyderabad's location is not available. You can opt for Chennai or Bangalore. I agreed to the Bangalore location
while discussing salary; he said that HCL could offer a 35% Standard hike as per the market on the discussion, and I agreed to the hike that the company offered. The discussion was closed later. HR said that I would send a salary quotation and Location preferences to the concerned team, which needed to be approved and would take a couple of days, then days passed, and I was waiting for my offer letter, thinking that I had got a Job in HCL .. no further communication from HCL

I called My HR, who I spoke to earlier upon calling so many times. She responded one day, she took all my details and verified with the Concerned department and said that my salary was not approved, which I agreed with what the company could offer as a standard hike.
I don't understand what approvals are needed to approve the salary that HCL wanted to offer for my level of experience. Please, HCL, don't waste our time by conducting interview/further exam discussions and not releasing Offer letters.

for some people job may be necessary at times if you don't want to hire people don't give any hope and I wanted to know why offer letter is not released please let me know if you require any further documents