Having troubles recovering a backup

Welcome to the forum @Alex_Turner

is the last step of several steps that I suspect weren’t done. The decryption happens at
Downloading all remote files using the Recovery Tool. For an overview of the steps, see
Recovering by using the Duplicati Recovery tool or run RecoveryTool’s help command.

If CLI RecoveryTool is not independent enough, see below for a little-used Python script:

Independent restore program