Tenant not handed over the keys

Hello everyone, We rented out a shop, and the tenant had been there for the past 20 years. Initially, we took an advance payment of 1 lakh 5 thousand rupees, and he was paying a monthly rent of 8 thousand rupees. However, there was no lease agreement or any formal paperwork. When we asked the tenant to raise the rent, he refused, so we asked him to vacate the property. Since then, he stopped paying rent. When we offered to resolve the matter, he falsely claimed that we owe him 1 lakh 30 thousand rupees as the advance amount. The tenant continued to stay in our property, claiming that the rent was being deducted from the advance payment. Eventually, he stayed until the balance reached 1 lakh 36 thousand rupees. He then locked the shop and refused to return the key to us. When we requested the key and the remaining balance, he not only refused but also demanded an additional 30 thousand rupees for the items he installed in the shop during his tenancy. What can we do in this situation?