Yep. I've had this issue as well. Tried to link so that I can report issues in the future via Discord if/when Railway login issues happen in the future.

I keep getting oauth failed on my MacBook and on my phone. On the phone I got the button not working mostly in the discord web view. I opened it in safari to be able to continue—but still got to oauth failed in the end.

But for me , I’m getting an error tooo. weird thing is I can see in user settings that it’s connected, but it’s not showing up on discord.

It worked for me when I used the discord desktop application. I was previously linking off the website, so it's possible that's the issue.