I suggest check your application code if you are setting at the reads you are doing (for this specific read functionality).
Further, I think you can tell more about your application and the code you are using for this functionality:
As per our architecture, the first request will fetch the document by using findbyid() method and ready to update content and save to db. After 200 or 300 milliseconds difference the second request will come and try to fetch the same document, that time I could see the document having old value. It will happen intermittently not all time. if am setting delay between the requests it never happen, without delay it will happen sometimes.