Can't purchase Riot Points

Hi!!!

I've been trying to buy riot points for like eternity now. And after adding all my card details, I get a msg stating - "You have encountered an error. Please try again later"

I'm from India and while installing LOL, I chose North America (Is this a problem?).

I checked online and found something about Internet Explorer issues. I currently have windows 10 and using Edge browser.

Any suggestions???