Previous Year Cash Bonus not paid to me after my resignation.

Sir, Annual Cash Bonus Component included in my CTC. I have joined in March 2022 and stays in company whole year and resigned in April 2023 So i have fully completed 1 Year. After 1 year i have not received Annual cash bonus so i have asked HR about the time of amount disbursement but HR not disclosed date and told that date is not finalized. I have resigned and after just 5 days of resignation, other employees received bonus but i didn't. I have told HR about it and they told that i am not eligible because of resignation and in notice period. this clause has not been mentioned in Offer letter or appointment letter. It is only mentioned in policy which was given only after joining. Can i take any steps to get the bonus? is there any legal action we should take because i think its wrong. company is fooling the employee by not mentioning anything in offer letter or appointment letter and by not disclosing the date. Please guide because almost 20% amount of CTC is hold in Bonus amount.