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"username" should be a valid email Id.
"provider" is an Optional parameter.
"suspended" is an Optional parameter.
"roles" is an Optional parameter.
"avatarSrc" is an Optional field.
”personaType” can be an ID or a name. For example, "personaType": "58c0587dc01db80f0019163c" or"personaType": "Administrators".
If you don't specify personaType while creating a user using the User Manager node, the user will be created under the “User“ persona type.
Update
You can update an existing record with this option
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