The numbers shown in your Mettle app are provided from your connected FreeAgent account. Complete any outstanding actions you might have in FreeAgent to get the most up to date view of your tax.
If you want to see your tax calculation in detail you can view more in FreeAgent by:
Selecting the tax type you want to learn more about on the Tasks tab
Select 'How was this calculated?'
Select 'Visit your FreeAgent account'
Login to FreeAgent
If you have any further questions about your tax calculation please contact FreeAgent directly.