Kalyan Jewellers — Wrong calculation for customers

I made a purchase from Baroda outlet.
I also offred my old ornaments.
Old ornaments were melted and machine identoified 84% purity of gold.

At the time of valuation of old gold it was calculated at 84% of prevaling 22 CT gold rate.

I am of the opinion that when purity is identified at 84% of gold the value of gold should be calculated at 84% of prevaling 24CT gold rate.