SvelteKit 404 API Error

[404] POST /api/auth/sign-in/social
Handling request for: /auth/register 

import { auth } from "$lib/server/auth";
import { svelteKitHandler } from "better-auth/svelte-kit";
import { building } from "$app/environment";

export async function handle({ event, resolve }) {
  console.log("Handling request for:", event.url.pathname);

  const session = await auth.api.getSession({
    headers: event.request.headers,
  });

  if (session) {
    event.locals.session = session.session;
    event.locals.user = session.user;
  }

  return svelteKitHandler({ event, resolve, auth, building });
}

await authClient.signIn.social({
  provider: 'github',
  callbackURL: '/'
});