Cannot buy Riot points

Wanted to buy RP to shop in the "Your Store". Tried the first option, no joy, different error messages pop up, like:

Failed to load URL "https://plstore.euw1.lol.pay.riotgames.com/session/new/" with error "ERR_NAME_RESOLUTION_FAILED" (-137).

Trying PayPal, but selecting buttons were gone, and now I cannot even enter to purchase RP, it crashes instantly. Clicked "Report the Bug" in a client, and it takes me to the empty page, with a Heimerdinger background only. Same thing here: https://pbr.leagueoflegends.com/ and here:
http://pbr.pbe.leagueoflegends.com/

With this kind of a total system crash I wonder if what we already purchased is safe at all.