iBall — iball service center sp road bangalore

Address:

Shree Ram heights apartment, top floor, door number 301, Chikkalasandra, Bangalore, Karnataka, 560061

I had given my iball slide co-mate tablet for repair on 6 june 2017 for changing the touch screen. The cost for changing the screen was 600 rupee. They said after 7 days i can collect it. Today 22 june they called me and says my tablet pcb is not working and asked me to pay 5000 rupee.
When i started arguing that everything was fine when i gave they said to call me on monday. The location of the service center is sp road bangalore. Please find attached the invoice.