MessageAction isn't set, the default is to send a welcome message via email or phone (SMS).AdminCreateUser with SUPPRESS for the MessageAction parameter, and Amazon Cognito won't send any email. FORCE_CHANGE_PASSWORD state until they sign in and change their password.AdminCreateUser requires developer credentials.curl --location --request POST '/' \
--header 'X-Amz-Target;' \
--header 'Content-Type: application/json' \
--data-raw ''{
"User": {
"Username": "string",
"Attributes": [],
"UserCreateDate": "string",
"UserLastModifiedDate": "string",
"Enabled": true,
"UserStatus": "UNCONFIRMED",
"MFAOptions": []
}
}