Landlord has not refunded the full security amount

Hello Sir/ Ma'am, I was staying in a rented flat since April 2016 and was paying rent ontime to landlord. The rental agreement was for 11 months with a clause of 10% increment in rent on renewal. First renewal took place in April 2017 with 10% increment in rent. Second year renewal was due on 31 March 2019, but before renewal we decided to vacate the flat and requested landlord to stay in flat till April 20, 2019. On mutual agreement I had paid the rent to him for 20 days (13350) as per the march month rent ( 20,000 pm). On vacating the flat, he had deducted 1300 from security on ground that rent was supposed to revise on April 01, 2019. Since there was no formal agreement signed for the revised rent and it was just an over stay of 20 days with his verbal consent after expiration of previous year rent agreement. I'd like to know in the court of law, was he entitled to deduct this extra 1300 from my security when he had agreed on my request and I paid the 20 days rent in the begining of the month as usual. Please help.