Landlord not returning my advance even 15 days after my vacating

Dear Sir, I had been asked by my landlord to vacate the house within a mere 17 days of stay citing the reason that he is returning from US and would need it for self. There was no formal agreement made before that despite several requests from my side. I clearly sense that it was a conscious decision from his side to rent his flat out to me on a temporary basis with a hidden intention to get it back with a one month notice as is the general practice. Though it was immensely troublesome, incurring a lot of unwanted expenditure, I had vacated the flat within 17 days as he had repeatedly asked me to move out quickly. To give you the context, he had asked me to pay the previous tenant (who was also my acquaint) on behalf of him an amount of Rs 28200, which I had paid through NEFT and additional 5000 to the landlord himself as token advance. I have the proof of his request on whatsapp and the acknowledgement of receipt of amount by the tenant. There is also a third person whom he had appointed as power of attorney in his absence. I can consider him as additional evidence for my advance amount payment. Now the problem is that he is not returning my advance amount fully. He has refunded Rs. 20000 so far and is supposed to refund the remaining Rs. 4748. He didn't refund the same then and agreed that he would return it after 15 days as he is travelling to hometown. I too agreed to it in presence of my friend as witness. Later he started coming up with silly reasons everyday on whatsapp, for deducting pockets of amount from this remaining amount. I questioned him about the mutual agreement we had in front of my friend. He then says that he is not going to refund any amount and I can do whatever I want. I still maintained patience and asked the third person who has the power of attorney, to speak with him. He suggested me to wait till the date he agreed up on. Now it has been more than 16 days (crossed the date he agreed upon refunding my money) and I have not got any response from him so far. So, I have sent him a notice on whatsapp and email asking him to refund the amount today, else I would be taking this up legally. Have not got any response so far. I, along with my family are really troubled by this person both mentally and financially. I want to pursue the compensation for all the trouble he has caused so far. Please suggest me the due course of action.