Add Group Members does not work

[jdocampo]

Describe the bug
It is not possible to add group members through the labs.graph.add_group_members.
It raises a 400 Bad Request.

To Reproduce
Steps to reproduce the behavior:

1. Use this snippet:

users_group = "some uuid"
user_id = "some uuid"
labs.graph.add_group_members(group=users_group, user=user_id)

Expected behavior
User is added to the group

Screenshots

Desktop (please complete the following information):

• OS: Windows 11
• Browser: Edge
• Version 145.0.3800.58 (Official build) (64-bit)

Additional context
Error:
FabricHTTPException: 400 Bad Request for url: https://graph.microsoft.com/v1.0/groups/00346b7f-2db4-4894-a7bf-b1a899a92b64/members/$ref Error: {"error":{"code":"Request_BadRequest","message":"An unexpected 'EndOfInput' node was found when reading from the JSON reader. A 'StartObject' node was expected.","innerError":{"date":"2026-02-17T11:42:29","request-id":"baecf420-8bce-44e4-bc45-f899ce969470","client-request-id":"baecf420-8bce-44e4-bc45-f899ce969470"}}}