3829200 - [ADP] Why have I received an email stating that the file was not received when the ADP HR Connector Employee Import runs?

For the past two days, I've received this error: File for Employee Import not received. Could you be of assistance? Attached is a screenshot of the email I received. 

The client received an email from AutoNotication@concursolutions.com stating that "This email is to inform you that a file was not received by YYYY-MM-DD HH:MM:SS GMT for processing. The job will continue to run as scheduled and will process files when they are received." , KBA , CON-INT , Integrations , Problem