Insertions throws "Document String has change vector B:44-FJLAj, but Put was called with expecting new document" from RavenDB using .NET6

Question

Below error is thrown while inserting a new record in RavendBD using .NET6.

Is it because the same id already exists in the RavenDB or there is any other things that need to be taken care explicitly?

{
  "message": "Document String has change vector B:44-FJLAj+/nuk+XMaK239q93w, C:45- 
  g4fL0AQJvkqqH0a3fl/0xw, A:63-it/GlSrkfkKOWb/7tSvx1A, but Put was called with expecting 
  new document. Optimistic concurrency violation, transaction will be aborted.",
  "errorList": [],
  "isSuccess": false
}

Please let me know if more stuffs is required to support the question.