If you want to cancel or stop a Solicitation, this option can be found on the Procedure tab of the left hand menu (found when in your solicitation on the Settings Tab)
By clicking the 'Edit' button below, the link: 'Cancel Solicitation’ will be shown .
By clicking the link, your solicitation will get the status 'Canceled' and will be archived.
The time of your cancellation will be registered right behind the link in date and time.

It is possible to undo the cancellation of the solicitation. This can be done by going back to the solicitation Settings - Procedure and then selecting "undo cancellation" behind the edit button.