Maybe they are somehow implementing the Amazon websites limits, which are as follows
- 30-days: INR 30,000
- 60-days: INR 40,000
- 90-days: INR 50,000
- 365-days: INR 3,60,000
But I don't know how will they even know other than maybe using the Credit card.
Did you somehow hit any of the limits as above with the same CC?