Can no longer access switch online

[bit-whisperer]

Adding an account through the Nintendo website makes Lounge Desktop produce this error:
An error has occured while adding account: { "text": "9427\nUpgrade required." }.

is this an api issue?

[subnode]

Thank you for opening issue.
Yes. f token generation method has been changed since Nintendo Switch Online app v1.4.1.
It seems nobody figures out generation algorithm of new f token.
Some application (such as ikaWidget2 and splatnet2statink) generates f token by using external Android server.
(c.f. splatnet2statink #62)

Technically this application can use the same way, but I have to contact that server's admin first.