Nintendo switch bought online but can't go online?

Sa
- in Nintendo
5

I got nintendo switch online for 20 euro but can't go online in Super smash bros ultimate error code: 2618-0521

Ze

Your NAT type is probably not open.

Sa

What should I do?

Ze

Can have several reasons. Enable ports in router, disable UPNP.

Sa
1

Strange is only that it is common with a character and all other onl e games 1vs1 go too

Ze

What?