It might because something else is using port 3000

You can kill the port 3000

I have my live app running on 3000 yes

Then restart next js

Oh ok

it needs to stay there

but i want to use 3001

how do i do that

my paylaod

{
"url": "http://localhost:3000/api/auth/error?error=CredentialsSignin&provider=credentials"
}
the response

Is anything running on 3001?

Is the server live

For 3001

yup

that's where I'm logging in from

@Netherland Dwarf it does work in npm run dev

any places where i should look in that casE?

Hmm im not sure sorry.

you can kill 3000 if you want to use 3000, otherwise you can swap your dev script in package.json to "dev": "next dev -p 3001", to get port 3001