We apologize you have been unable to schedule your email campaigns as easily as you should! We have taken a look at your account and can see there are currently two emails scheduled to send. Were you able to schedule your emails after all? This experience you have described is something we are continuing to troubleshoot. At this time we recommend any users receiving this error message to create a copy of the campaign and attempt to send or schedule this copy instead. Are you able to schedule your email following this workaround?