signInEmail isn't properly setting cookies in production? (NextJS 15/Vercel)

Hello, I'm using Vercel to deploy my web app and everything works fine when I'm not working with a production environment or when I don't use 'useSecureCookies'. I believe that when I try to sign in via email, the cookie is not being properly set.

In auth.ts:
I have nextcookies() in my plugins and it's my last one, and I have crossSubdomainCookies activated.

In my client component for login, it's calling a server action signin.ts:
"use server"; import { auth } from "@/auth"; export const signIn = async (email: string, password: string) => { console.log("signing in..."); try { const response = await auth.api.signInEmail({ body: { email, password, }, asResponse: true, // returns a response object instead of data }); console.log("response from sign in", response); if (response.status === 200) { return true; } else { return false; } } catch (APIError) { console.error(APIError); throw APIError; } };

In my middleware, I'm fetching the session this way:
console.log("cookies", request.cookies.getAll());
const getSessionUrl = BASE_URL + "/api/auth/get-session"; console.log("getSessionUrl", getSessionUrl); const session = await fetch(getSessionUrl, { headers: { cookie: request.headers.get("cookie") || "", }, });
When I am in production, the logs show that there are no cookies.
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