HCL Technologies — Issue with offer letter and No response from management

I gave an interview in HCL and after clearing all the rounds had the salary discussion. A few days later, I received an email stating that my salary cost had been approved, and I was advised to wait two weeks to receive an offer letter.

1st Round held on 14th June,
2nd round held on 16th June.
Cost approval mail on 20th July.

I announced my resignation from my current company. Right now, jobless.

No response from HR, I have called so many times and so many emails. I am following up with HR continuously but he is not replying and didn't receive any updates from the management.

I am currently mentally very stressed and depressed.