Why can't the video be uploaded to my phone?

You must close the open video before you can copy it.

There are many ways to upload a video to your phone, the most common and easy way is to plug the memory card into your computer through a card reader and copy it; the other is to connect to your computer with a cable and copy it directly in high-capacity mode; to transfer it using a PC suite; or to transfer it using a Bluetooth suite if your phone supports Bluetooth.