Why will this code not work?

 // When user logged in, log the user in the console
  callbacks: {
    async signIn(user, account) {
      console.log(user.profile.email ?? "no email");

      const findUser = await prisma.user.findUnique({
        where: {
          email: user.profile.email,
        },
      });

      if (findUser) {
        console.log("user already exists");
      } else {
        console.log("user does not exist");
      }

      return true;
    },
  },