Good Day,

I recently made a purchase for 30$ worth of Onigiri Coins.
When I logged into the game the window popped up showing them but I accidentally hit the Esc key.
Now I don't know how to receive my coins. . .

Log in, open Shopping Plaza, wait for prompt to receive OC, don't hit Esc this time. If that doesn't work... I guess submit a ticket to CS.

I'm still trying to figure out how you managed to hit the Esc key. There's literally no reason to even have your hand anywhere near there.