Domino's Pizza — Billing Discrepancy - False Billing

I am a regular customer of Domino's. Today while ordering pizza through Domino's App, I found there is a fraud being done by Domino's.
I ordered 3 items wherein the total amount was Rs 379.00, wherein Rs 16.38 was GST and Rs 35.00 as Delivery.

I applied a discount coupon of Rs 50.00, the total amount after discount was Rs 336.00, where GST of Rs 16.38 was reduced to Rs 13.88 and Delivery charges of Rs 35.00 was increased to Rs 45.00, which is surprising.

Thirdly, if the amount is being paid online, Domino's billing software converts the amount to rounded-off, which is an unfair means.

Therefore, I request to have necessary action on the fraudulent billing practice being done by an American pizza company Domino's.