Please go to the Configuration page and set the Log Level to "All information and debug". Take a new backup, then ZIP and attach the log file here. It will give us more context on what is going on.
While you are at it please double check the Directory you've set up in the FTP configuration of Akeeba Backup. Keep in mind that as the component tells you the "Test FTP Connection" button only checks if the hostname, port, username and password are correct. It doesn't test the directory. If the directory is incorrect then you will get the error message we see in your screenshot.
Moreover, do keep in mind that the FTP configuration is per backup profile. If you have more than one profile please make sure that you have made all changes in all of the profiles you want to use the FTP upload with.
Nicholas K. Dionysopoulos
Lead Developer and Director
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