Nintendo Switch Fortnite login is not working?

I have Fortnite on the switch and I want to play it as well. It will open a window where it says that it is necessary to use this service with the Nintendo account, that jmd the 18 is set the account as supervised and allows to share the Acount information. I have already done everything. But if I hit OK, it says, "Login failed, you can't sign in to your account for Nintendo Online Services. Please try again later."

I do not know how to continue. Can someone help me?

Hi, create a completely new account with which you are over 18, so it's then otherwise try a software update of the switch and then check for updates from Fortnite!