The Roon Arc app downloaded to both my iPhone and iPad is not recognizing my Roon username and password. I have 2.0 installed on a Nucleus + and have updated my Roon apps on both my iPad and I-phone and also on my PC. Not sure what the problem is or how to proceed to fix it.
Have you checked that Roon ARC will be able to reach your Core when you are outside of your home network? In Roon, Go to Settings > Roon ARC and check if it is ready.
It’s strange that you are not seeing a detailed error message (check out the Help article I reference below). Perhaps you could click/touch the Reset link by the Port number to try again?
Also, please give full information to the points below below so that Support can help.