Here's how to delete all your data from FreeAgent. Use this option with great care, as it can't be undone!
How to delete all data
Head to Settings, and choose Delete All Data.
The Delete Data screen appears.
Fill in the boxes. In the first box write DELETE MY DATA and in the second box your FreeAgent password, like this.
Then select the Delete Data button.
FreeAgent will show you this screen as your data is deleted.
Then once your data is fully deleted you'll be returned to the beginning of the Getting Started process.