It has this error but it's likely not valid:
[05/07/17 21:11:00.411][DEBUG] [Sequence Thread] Cannot start seqeunce. No active targets.
You can try
Ctrl+R which will reset the sequence status (clearing any completed exposures and starting fresh) and should remove the sticky state from your last target.
If you can also attach the sequence prior to doing this we can double check if something else is holding it up.