Mutually Terminated Rented Agreement Yet Owner Deducted Amount From My Deposit

I lived away from home in another city for work. It had been only 10 days since I started staying in the said property on rent after which, as a precautionary measure my company announced strict WFH in this Covid-19 outbreak. I went to my hometown as the internet was not available in the rented apartment. Little did I knew that shortly after the nationwide lockdown would be announced in March. Hence I became stuck in my hometown. My company has also further extended the WFH policy for an indefinite time and I realized that the rented property has become un-useful and I was paying rent for an empty apartment. My owner agreed to terminate the contract without any contesting thought. I have also vacated the premises of the rented apartment in May. It was mutually agreed that the owner will refund the entire deposit along with the rent of Jun to Aug 2020. The owner refunded the deposit amount after deducting the rent of JUN-AUGUST stating the lock-in period clause. We have done an online rent agreement.