The sftp server is available on the following locations for sandbox/test and production.
Sftp host's for the different environments
Production: sftp.prd.trustly.cloud
Test: sftp.sbx.trustly.cloud
It's used both for the batch processing as well as for reports.
Important: The private key is extremely secret and should only be kept by authorised personnel.
Then you connect to the SFTP server like this
sftp -i your_private_key.pem your_accountname@sftp.prd.trustly.cloud
cd batch // or cd reports
get/put file
Once there, use the normal ftp commands to transfer files to and from the server. How long the files are kept on the server varies from folder to folder, see the different sections for retention periods.