Putty - pscp - "Connection Time out"



I have created a SSH tunnel to an external (i.e. hosted outside my home
network) and have succesfully remotely logged onto the server.

When I try to use the pscp command to copy a file to the server I get
the error "Fatal: Network Error: Connection timed out"

Can anyone advise on what may be going wrong / how to resolve it?

TIA

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