Invalid `prisma.user.findUnique()` invocation:
{
  where: {
    id: undefined,
?   email?: String,
?   username?: String,
?   stripeCustomerId?: String,
?   AND?: UserWhereInput | UserWhereInput[],
?   OR?: UserWhereInput[],
?   NOT?: UserWhereInput | UserWhereInput[],
?   createdAt?: DateTimeFilter | DateTime,
?   updatedAt?: DateTimeFilter | DateTime,
?   isPayed?: BoolFilter | Boolean,
?   isJoined?: BoolFilter | Boolean
  }
}

const user = await getUser();
  // Check if a user with the given email already exists
    const existingUser = await prisma.user.findUnique({
        where: {
            email: user?.email || "",
        },
    });
  if (!existingUser) {
    const new_user = await prisma.user.create({
      data: {
        email: user?.email,
        isPayed: false,
        isJoined: false,
        // id: user?.id,
      },
    });
  } else {
    console.log("User already exists");
  }
  const currentUser =
    existingUser ||
    (await prisma.user.findUnique({
      where: {
        email: user?.email ?? "",
      },
    }));