Hyundai - Excess MV tax deduction in BH series due to fault of dealer

I noticed a bigger issue/mistake in the registration system of Hyundai w.r.t BH series registration. I am a PSU (ONGC) employee and I opted for the BH series registration number in Nov’****. Hyundai charged me MV tax of INR ***** (Invoice attached) while all the other companies (Maruti Suzuki, MG, Volksvolan) charging only ***** rupees approx. for the same segment of cars. This issue has arised because as per the government guidelines, tax should have been calculated on the invoice value without GST for BH series registration. However, concerned person from Hyundai dealer responsible to fill the registration details filled the invoice amount including GST and tax calculated on the wrong value and hence all the customer including me had to give more money than applicable amount(applicable amount in my case is ~***** INR. My colleagues have also taken the BH series no. (Maruti Suzuki, MG, Volksvolan) but they paid very less amount for registration, in comparison to what Hyundai has taken for registration. I am attaching here the gazette notification copy for BH series registration, point *, ** B. Principle for motor vehicle tax in which it is clearly mentioned that tax should be calculated on the invoice value excluding GST value. all the customers who are taking BH series no. for Hyundai vehicles are charged more because of an error in the registration system of Hyundai. It is a huge financial loss to us as a customer on behalf of the mistake made by the Hyundai motors. I have written mails to Hyundai at crservice@hmil.net and also to Koncept Hyundai at Manish.gandhi@koncepthyundai.com but no firm response has been received from Hyundai.