Cannot read properties of undefined (reading 'substring')

선생님 api/auth/signin 으로 가면 해당 에러가 나옵니(사진)다

Cannot read properties of undefined (reading 'substring')

import NextAuth from "next-auth"; import CredentialsProvider from "next-auth/providers/credentials"; export const { handlers: { GET, POST }, auth, signIn, } = NextAuth({ pages: { signIn: "/i/flow/login", newUser: "/i/flow/signup", }, providers: [ CredentialsProvider({ name: "Credentials", credentials: { username: { label: "Username", type: "text", placeholder: "Username" }, password: { label: "Password", type: "password", placeholder: "Password", }, }, async authorize(credentials) { const authResponse = await fetch( `${process.env.NEXT_PUBLIC_BASE_URL}/api/login`, { method: "POST", headers: { "Content-Type": "application/json", }, body: JSON.stringify({ id: credentials?.username, password: credentials?.password, }), } ); if (!authResponse.ok) { return null; } const user = await authResponse.json(); return user; }, }), ], });

Cannot read properties of undefined (reading 'substring')

(사진)middleware가 보여서 남겨봅니다

Cannot read properties of undefined (reading 'substring')

(사진)

센세.....강의에 오류가 너무 많이 나는데 어떻게 해야 합니까??

비디오 상세페이지

선생님 어제 서버 문제였던거 같아요 오늘은 잘 되네요