Splatoon 2 doesn't function

Hello,i'm new in this community so i don't know if i can post this. When i try to enter in a matchmaking of splatoon this message appear(it's in italian) Here the translation= "Error code:2618-0513 It wasn't possible to connect whit any console. A error occurred whit the NAT traversal. Try later If the problem persists,the condition of your network may be not suitable for playing online in a stable way"