Connection problem

I have used SmartFTP for a while, but it suddenly stopped working. The support staff vaguely indicated that they had done some unspecified software update, and that the new software rejects the IP address or something about the origin of the connection. The string I get is like this:
[21:23:01] SmartFTP v3.0.1038.0
[21:23:03] Resolving host name "gpu.unbc.ca"
[21:23:03] Connecting to 142.207.144.42 Port: 21
[21:23:03] Connected to gpu.unbc.ca.
[21:23:25] An established connection was aborted by the software in your host machine.
[21:23:25] Server closed connection
[21:23:25] Connect failed. Waiting to retry (30s)...
[21:23:55] Connection attempt 2...
[21:23:55] Resolving host name "gpu.unbc.ca"
[21:23:55] Connecting to 142.207.144.42 Port: 21
[21:23:55] Connected to gpu.unbc.ca.
[21:24:16] An established connection was aborted by the software in your host machine.
[21:24:16] Server closed connection
[21:24:16] Connect failed. Waiting to retry (30s)...
[21:24:46] Connection attempt 3...

etc etc
I have read a bunch of threads but can't seem to get anything that is similar, or at least not that I recognize as similar.
Supposedly there is some way to reset the SmartFTP so that a new connection can be established. Can anyone help?