Vidhya — Boarded bus and paid but conductor not given tickets

I have boarded bus KA-35-F-333 at Goraguntepalya. I have paid the conductor 500 for 2 tickets to Tumkur. He gave back change of 340 but had not given tickets. I have been chasing him but now he says he gave me the ticket. Upon following with him again, he's asking me to buy tickets again. Can someone please help in this