After my exit can employer have rights to debit from my salary account without my permission?

I have informed my Manager on Oct 8, 2020 about my resignation as I will be leaving for higher studies, however due to pandemic situation the approvals have arrived on Oct 15,2020 with release on Oct 17, 2020. I was suppose to serve one month notice period which in need had turned out 3 days and remaining days to be adjusted with my leaves. I received a NDF (No Due Form) form stating my release date to be NOV 13, 2020 since the manager had promise to handle them accordingly and following which I have received a amount credited for month of Oct, Nov + F&F (full and final settlement) at the end of NOV, 2020. Now, after 6 months of my exit, the HR comes back stating that I was wrongly credited for the month of Oct & Nov and need to repay for 15 days of Oct and entire month of Nov. In addition, my release date changed to Oct 17, 2020 with missing notice period days i.e. 27 days were indeed under recoverable in the F&F form received. With the amount credited and needed to be recovered my Full & Final settlement is repay of Rs.72,000 which I am unable to understand because my F&F benefits + Oct salary seems to be just Rs.7,420 from the amount credited previously. 1. Do the employer have rights to debit the amount from salary account without my approval? 2. If the glitch was created from their end and as I dont have proper clarity, do I need to repay the employer? 3. Can there be any compensation possible as the amount credited in Nov, 2020 has been used thinking that it is my full and final settlement.?