Landlord is not returning proper security Deposit

I have taken house for rent from April 1st 2019 to July 30th 2020 in Bangalore. As per Rental agreement of 11 months I payed a security deposit of Rs. 1 lakhs and payed every monthly Rs. 18000 rent. As Corona cases are increasing and I am planning to work from my native, I decided to vacate my rented house and informed my landlord that I will be vacating my house on 20th July 2020 and I shifted from that house on 25th July. Now as a part of final settlement, my landlord is saying he will return Rs. 42000 of my security deposit. His calculations are like July 2020 month rent Rs. 18,000 plus one month Maintainance Rs. 18,000 as per agreement which I completely agree. Apart from that he is charging August 2020 month Rs. 18000 giving reason that, I am vacating my house on short notice. Even rental agreement was for 11 months, which got over in April 2020 month. He is charging a total of Rs. 58,000 which includes 3 months rent and Rs. 4000 for kitchen tap repair. But I felt cheated because he is charging for August 2020 month also.