I just bought a new Roku Express+ for my daughters room and when I went to sign into my Roku account it just says “We’re sorry, the email you provided isn’t working” it works on my TV and I retyped it multiple times.
Roku is having some service issues at the moment: https://downdetector.com/status/roku/
DBDukes
Roku Community Streaming Expert
Note: I am not a Roku employee.
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I ran into the same thing. There was a problem at Roku's end with the activation system last evening (15 April, 2021). It was fixed after an hour or so.