Organisation reduced my notice period from 90 days to 10 days after my resignation with no pay

I worked with Heritage foods limited, Hyderabad. I was working hard and was also appreciated vua mail, letters and certificates for my performance. I was working from home since March'20. November onwards HR sending us mail to again come back to Hyderabad or else each day will be marked absent. Due to pandemic, my family was not ready to send me to Hyderabad all alone again. Hence, I resigned on the 2nd day, 17th Nov, since the days were marked absent for WFH employees not resuming to HO Hyderabad. I had 90 days notice period. I refused to relocate due to pandemic but was ready to serve notice while WFH. After 7 days I got a mail that next day is my last working day at Heritage. I was shocked as there was no discussion with me on the same. 31 Oct I was given performance letter for FY 19-20.Now, when I contacted HR, he claimed that my reporting manager questioned my performance (31st Oct it was all praises). When I asked about notice pay, HR said, you will be paid till your last working day only. He also stated that I should be grateful that I will not be asked to pay 3 months gross salary to the organisation. My aapointment letter states "After such confirmation by any chance in case you wish to leave the services of the company or vis-a-vis, you have to give three months notice or three months gross salary in lieu of the same" I feel, he tried to misguide me here. Please let me know what are my rights here in terms of the notice pay.