Employer denying to clear Full and Final Settlement

Hi Kalaiselva sir, I have resigned from a company on 29th Feb 2020 and as per the compensation(Hike) letter received in April 2019 it is mentioned that I will be getting Retention bonus and Variable pay of total 2 lakhs if Im under the payroll of the company. Scene 1: Since I resigned on 29th Feb 2020 company didnt accept my resignation,and since due to COVID pandemic i was relived 1 month early(90 days of notice period) stating that Im serving notice period,even though my resignation was not accepted by the company. Scene 2: Post reliving I was told by HR that Iam not eligible for Retention bomus since i resigned before financial year i.e., March 2020 but Iam eligible for Variable Pay which will be paid in July2020 also Full & Final Settlement Letter states the same whcih is signed by CEO of the company. When I asked for variable pay, HR was very rude and stated that Im not eligible for Variable pay because company decided not to pay for the employees who are out of the company. When spoke to management I got a reply stating that Im not in the company at the time of payment. But neither the HR nor Management is justifying for FFS and the mails sent by HR stating that Variable pay will be paid in July 2020, rather got a mail from Company legal advisor stating that Im not eliglible for Variable pay which was communicated by HR but im still demanding for that and i need to stop asking for it. @Note : 6 times the company HR confirmed me that Variable Pay will be paid in the month of July 2020 in written email and also in Final Settlement letter dirctly signed by CEO.