Hello Gajendra Jangid,
Thank you for reaching out to Microsoft Support!
For your question, we just tested it in Graph Explorer, and it worked fine, with the following results:
It is recommended that you test it in Graph Explorer first to see if it can be created successfully and troubleshoot the naming problem for names.
Reference document:
https://learn.microsoft.com/en-us/graph/api/group-post-groups?view=graph-rest-1.0&tabs=http
Hope this helps.
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