When you schedule an email in gmail it is supposed to save your email in the drafts folder until it sends. Nothing has gone wrong, but due to how we integrate with gmail this is a restriction of the scheduled emails that they have to stay in the drafts folder.
After it hits the scheduled time, they will move from drafts to Sent. You can see the email has been scheduled within toutapp.com and it should also have the label Tout Scheduled Email.
Alternatively you can schedule from toutapp.com and they won't show up in your drafts in gmail.