This can happen when you submit your request using Custom Scheduling.

It can take up to 12 hours from the expected end date of your request to receive the notification about the outcome of your observation and for the status of your request to change to Completed or Failed. 

Our systems are fully automated, from the telescope acquisition phase to the calibration and delivery of the images to you. 

Sometimes things don't go as planned, and your images might get stuck somewhere in the process. For instance, there might be a delay in the data upload due to bandwidth restrictions. Or your images might fail our automated quality checks.

When this happens, we manually inspect your images, and, if everything looks good, we deliver the images to you.

Often, however, the failure is just due to poor weather. Even when the images are not acquired due to poor weather, you can still experience a delay in the notification. 

We are aiming to soon improve this and report the completion status as soon as your request is expected to complete.