To cancel a subscription, 

1. Goto the Sortd settings dialog (cog at bottom left of Sortd in fullscreen) and click on Account.

2. Select the Organisation, based on the subscription plan or PowerPack you wish to cancel. This will open a new dialog with "Billing and Members"

3. Under Organisation Users you will see the number of members in the subscription and the status of the subscription. Click "Cancel" to cancel the subscription.

4. Repeat for any other Organisations/plans