No bill issued for mobile repairing and no refund - King's Mobile Servicing Centre

I gave my Samsung Galaxy Grand Quattro mobile phone for replacing the cracked display and touchscreen in the above-mentioned shop on 05/03/2018 at about 9.pm. The shopkeeper charged Rs.1,600/- for repairing the same. It took about half an hour to repair the phone and the shopkeeper handed it over to me. When I asked for a bill he told that there is no bill book for the shop and that they do not usually issue any bill or receipt to any customer. While handing over the mobile phone, the shopkeeper assured me that if any error occurs I can bring back the mobile to the shop and the same will be corrected by him. And the very next day I found that the display of the mobile phone keeps flickering whenever I tried to use the mobile phone. I informed the shopkeeper about the same and asked him to get it repaired. Then he replied that he will be out of station for two weeks and asked me to bring the mobile phone afterward. Later on, when I took the mobile phone to the shop, the shopkeeper told me the flickering of the mobile screen was due to the phone's battery and that has to be changed. And he added that he does not have a spare battery in the shop and that he has to obtain it from some other place. Hence he asked to bring the phone after he asks me to do so. I later visited the shop to know whether the shopkeeper had obtained the spare battery but he informed me that he was unable to obtain the spare battery for my phone. Hence I purchased a new battery for my phone from another town for Rs.480/- and used it. Even afterward, the complaint of the display persisted. Then I took the phone to the shop and informed the shopkeeper about it. He asked me to leave the phone with him overnight so that he can test the phone with the new battery and find out a solution. Later when I enquired about the phone the shopkeeper informed me that the error cannot be corrected and returned the phone back to me. Then I took the phone to another mobile repairing shop. The shopkeeper inspected the phone and told that the problem was with the newly installed display. Then I took the phone to the first shopkeeper (King's mobile servicing, Chungam) who repaired it. But he refused to either inspect the phone or refund the money. Instead, the shopkeeper started using abusive language and yelling at me. He threatened me that he would file a false complaint against me of causing damage to his shop. On this, I filed a complaint at the Town West Police Station, Thrissur. The Sub Inspector enquired about the complaint with the shopkeeper and he asked the shopkeeper to either repair the phone or to refund the expenses for the service to me. But the shopkeeper adamantly refused to do so. He keeps saying that I have not even entrusted the phone for repairing with him since he has not issued any bill. He is not ready to repair the phone or to refund the money.

King's Mobile Servicing Centre, Chungam, Ayyanthole, Thrissur, Kerala