Broken ftp transfer

I am trying to transfer multiple files from several directories on a remote machine. The structure is
/am/yyyy/mm/file1, file2, etc. mm ranges from 01 to 12. In the example below yyyy is 1969.

The log shows (after transferrinh hundreds of files):

226 Transfer complete.
PASV
227 Entering Passive Mode (130,246,191,168,138,95).
Opening data connection IP: 130,246,191,168,138,95 PORT: 35423.
RETR lfam19690419.nc
150 Opening BINARY mode data connection for lfam19690419.nc (9483764 bytes).
9482240 bytes received successfully. (112.93 KB/s) (00:01:22).
226 Transfer complete.
CWD /badc/.e40_daily_avs/am/1969
CWD /badc/.e40_daily_avs/am/1969
250 CWD command successful.
PWD
250 CWD command successful.
TYPE A
257 "/badc/.e40_daily_avs/am/1969" is current directory.
PASV
200 Type set to A.
CWD /badc/.e40_daily_avs/am
227 Entering Passive Mode (130,246,191,168,138,96).
PWD
250 CWD command successful.
Cached directory reloaded.
CWD /badc/.e40_daily_avs/am
257 "/badc/.e40_daily_avs/am" is current directory.
PWD
250 CWD command successful.
PASV
257 "/badc/.e40_daily_avs/am" is current directory.
227 Entering Passive Mode (130,246,191,168,138,97).
NOOP
200 NOOP command successful.
NOOP
200 NOOP command successful.
NOOP
200 NOOP command successful.
NOOP
200 NOOP command successful.
NOOP
200 NOOP command successful.
421 No Transfer Timeout (300 seconds): closing control connection.
Connection closed.
-----------------------

SmartFTP is not resuming the transfer, but I do not understand why. How can I make sure that smartFTP resumes transfers?

Thanks,

Mark P. Baldwin
mark@nwra.com