If your video won't send and/or you receive a message that you don't have enough space on your device, this means that you have low storage on your device, which is effecting the ability to capture and deliver your Purple Ocean videos.
To check this, go to your phone's Settings-->General-->About-->Available. If there's only a small amount of space left, you will need to free up space on your device in order to shoot videos with Purple Ocean.
You also need to check your available RAM storage. Having several apps running in the background can affect your ability to record and upload vidoes as well.