Hopefully, you'll never lose a deal, but if you do you'll have to mark it as lost.
In our web app on the desktop, you can do that from either the dealboard if it's a sales document or in the document summary via the document action menu.
How to mark a deal as lost through document action menu
Go to the active document.
Click on the three dots up in the right corner.
Choose "Mark as lost".
Make sure you want to mark the deal as lost. Once marked, it will no longer be active.
Make a lost deal active again
Once a document has been marked as lost you can't make it active again. You'll have to create a new version and send out that version to the recipient for signing.