Need clarification on error response from SharePoint CSOM API - Attach file to a list item‎

I've recently observed a CSOM API call, attempting to attach a file to a list item, failed with following error details:

• Error message: Cannot complete this action. Please try again.

• Exception type: Microsoft.SharePoint.Client.ServerException

Unfortunately the error message is not as descriptive as expected, hence I'd like to reach out to understand the actual root cause of this error, e.g. is this a transient error that I could just retry the operation and it would succeed? Though the message asked to try again, but to what degree should we retry, e.g. how many times, etc.