Got an error: Unable to read data from the transport connection when trying to get the MIME content of a Outlook message which has more than 25MB size attachments

Question

I am having a requirement to send an email by attaching an eml file using Graph API. To attach the eml file, I have to get the Mime content of the selected message.
I am using following code sample to get the Mime content of a message item.

  var content = await _graphServiceClient.Users[mailboxAddress].Messages[mailItemId].Content.Request().GetAsync();  

Above code works fine if the attachment size is less than 25MB.
If attachment is more than 25MB, I am getting following error response.

I need some recommended way to get the mime content of large message items.