Indian Railway Catering & Tourism Corporation [IRCTC] — Ticket fare

I booked a premium Tatkal ticket in the name of Savitri Devi in the train no. 02834 from Tatanagar to Vyara travel dated 18/11/2021. The price of the 3rd AC ticket was showing INR 1750 in premium Tatkal but amount deducted was INR 6955. Although I understand that it is dynamic fare but how has railway deducted this much amount in the name of dynamic fare as after booking when I checked the price of the same ticket, it was showing INR 1950. It seems to be an unfair practice as it did not show the price and there has to be limit on the max fare in premium also. Also, the Tatkal quota tickets are getting booked within 20-30 seconds but premium quota has availability even after hours of opening. I want a clear explanation regarding this and if possible a partial return on the amount charged.