createMembership with userId and without email

I execute the following command in the nodejs server sdk:

const createNewMember = await teams.createMembership(teamId, [], '', userId);

roles = empty array email = empty string

I get the following error message: "Invalid email parameter: Value must be a valid email address" However, in the documentation under "TeamsApi/createMembership" it says: "You only need to enter one of the following: User ID, email or phone number. Appwrite will primarily accept the user ID > email > phone number if you specify more than one of these parameters."

Why do I still need the email?