Panasonic — complaining about authorized service center guntur a. p.

Address:

Guntur, Andhra Pradesh, 522017

I went to guntur authorized service center to fix double lock safety mixture jar handle set. They collected total payment for handle set. But 2 days later when i went for collect it they fixed old parts like lock sets, base plate etc. Event they didn't inform the customers they fixing the remaining old parts. Without customer intimation how could they approach to fix remaining old parts, when they collection full payment for the set?