Hey everyone ⭐,

I developed a POST API endpoint to store a checkout session in my Redis database.
When testing locally, everything works perfectly.
However, after pushing the changes and checking the Vercel preview, I keep encountering a 405 Method Not Allowed error when calling the endpoint.

Next.js: "^14.2.14"
output: "export"

POST METHOD

export async function POST(req: NextRequest) {
  try {
    const checkoutSession: CheckoutSession = await req.json();

    if (!checkoutSession.checkoutId || !checkoutSession.userId || !checkoutSession.productIds) {
      return NextResponse.json(
        { error: "Missing required fields in checkout session" },
        { status: 400 }
      );
    }

    const serializedSession = serializeCheckoutSession(checkoutSession);

    const expiresAt = new Date(checkoutSession.expiresAt);
    const now = new Date();
    const ttlInSeconds = Math.max(0, Math.floor((expiresAt.getTime() - now.getTime()) / 1000));

    const redisKey = `checkout:${checkoutSession.checkoutId}`;
    await setRedisValue(redisKey, Buffer.from(serializedSession).toString("base64"), ttlInSeconds);

    const formattedExpiresAt = expiresAt.toLocaleString();

    return NextResponse.json(
      {
        message: `Checkout session has been successfully stored in Redis and expires at ${formattedExpiresAt}`,
        checkoutId: checkoutSession.checkoutId,
        expiresAt: checkoutSession.expiresAt,
      },
      { status: 201 }
    );
  } catch (error) {
    console.error("Error processing checkout session:", error);
    return NextResponse.json({ error: "Failed to process checkout session" }, { status: 500 });
  }
}