tried paying in foreign currency using card's conversion rate, but it still went back to default

[ChinLiang]

afterwards i tried this but it didn't help

https://www.paypal.com/sg/smarthelp/article/how-do-i-pay-in-a-foreign-currency-using-my-credit-card-...

there wasn't any option for me to pick and straight away made the payment... sigh, lost money to exchange again

appreciate the help if any, thanks