Just now I checked on Payzapp for Millenia cc, it has 4.1% inconvenience fee. I get 5% as feature of Millenia. So, it's 5-4.1%., where is the extra 5 coming from?
yes that applicable on 5% online sites (selected categories), smartbuy is separate and has separate cap or restrictions which applicable all hdfc cards not only swiggy.
as of now only tatanue cards has separate structure in smartbuy.