Custom SignIn Page for Resend Provider

[rafal-r]

Hey there,

based on this docs: https://authjs.dev/guides/pages/signin I am trying to build a custom login page for Resend provider.

My next-auth config looks like this:

export const { handlers, signIn, signOut, auth } = NextAuth({
  debug: false,
  providers: [
    Resend({
      from: 'Space Joe <[email protected]>',
    }),
  ],
  adapter: SupabaseAdapter({
    url: SUPABASE_URL,
    secret: SUPABASE_SERVICE_ROLE_KEY,
  }),
  pages: {
    signIn: '/login',
  },
  callbacks: {
    async session({ session, user }) {
      const signingSecret = SUPABASE_JWT_SECRET;

      if (signingSecret) {
        const exp: number = Math.floor(
          new Date(session.expires).getTime() / 1000
        );
        const payload = {
          aud: 'authenticated',
          exp: exp,
          sub: user.id,
          email: user.email,
          role: 'authenticated',
        };
        const supabaseAccessToken = await new jose.SignJWT(payload)
          .setProtectedHeader({ alg: 'HS256' })
          .setExpirationTime(exp)
          .sign(new TextEncoder().encode(signingSecret));

        session.supabaseAccessToken = supabaseAccessToken;
      }
      return session;
    },
  },
});

The problem I'm observing that is not aligned with documentation is that after calling the signIn function returned from NextAuth() I'm redirected still to http://localhost:3000/api/auth/signin?callbackUrl=http%3A%2F%2Flocalhost%3A3000%2F address. However my custom login page is correctly rendered there.
But I would like to see it under http://localhost:3000/login address after calling signIn.

Is there something I am missing?