Advance amount not returning

Hello, i have rented the house 8 years back for running a preschool with a deposit of 3,60,000/- & the rent to be paid in advance every month. i paid the rent for the month of April'20 & with this covid situation i told the owner to give me some time to pay the rent, he has called me in June and asked me to clear the 2 months dues & then take a month time & pay , Due to this scenario schools are not operative & don't know when the situation will be normal , i wasn't in a position to operate for till march so i have decided to vacate the house & informed the same to owner. he says as per the agreement i have to give 3 months notice so he will deduct pending rent & 3 months rent (for the notice period ) & return me the balance advance after i clear the electricity & water bill till existing period. i told him to deduct only the pending rent and electricity & water charges I have cleared till the previous month for the existing month after it gets generated i will clear, but hes not agreeing for any of these, the latest agreement which was made for three years i.e from 1st June'17. please help me is the agreement still valid & what can i do as this situation my only earning source is not there & each rupee is valuable.