SFMC134I Probable cause: Client process broken prior to the completion of the current command.
SFMC970I Recommended action: Evaluate the consequences and determine whether a retry is in order.
Explanation: The FTP API has reported that the client process has been broken. There are a number of things which may cause this (e.g. TCPIP stack failure, TCP connection DROPped, etc.). The user must evaluate the circumstances and consequences and determine whether or not to retry.