Titan Company — no price list for battery replacement

Address:

SADASHIVANAGAR, 560080

I got my titan edge battery replaced, but i am sure the world of titan store over charged me, because i could see the technician change the price manually on the booking system and there was no price list displayed anywhere. How could i trust or verify if i am charged correctly? Further, the technician also acted suspiciously as he wouldn't sign and stamp the bill until i would ask him several times. I couldn't even check the price online as even the model number of the battery was manually entered and i couldn't find it online. I was unfortunately scammed by a well-known company like titan.

Arjun
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