How do I access previously recorded game clip files on my Xbox?

How do i record the gameplay on my xbox one? i noticed that i had Ryse son of rome footage clips but i never recorded those or anything .. i played other games and didn't see clips for those saved on there ..

The help menu on Xbox One states:

To record what's about to happen:

1. Load your game, then launch Game DVR.
2. Select Start new clip. The Game DVR app records for up to 5 minutes, then adds the clip to
   My clips in the Upload app.

To record what just happened:

1. Load your game, and play as usual. When something cool happens and you want to record it, launch the Game DVR app. The easiest way to do this is by saying, "Xbox, snap Game DVR."
   
2. Select End clip now and choose how far back you want Game DVR to grab. You can grab up to the last 5 minutes.
   

Sounds to me like simply saying "Xbox, record that." only records the last 30~ seconds of what previously happened, whereas what you needed to do was the second option that I listed.

Btw - I don't really see how this would be "game specific"... Surely all game clips recorded would all be in the same file format?

After hard resetting my xbox one (holding down the power button on the console for 10 seconds) and rebooting, I am able to record clips again. The clips I had previously recorded remain lost, though.

And, just in case anyone else runs into this, I was not able to see the clips in Smartglass, either (and still can't see the missing clips), and I was set to Appear Online.

So when I play madden I can no longer say “xbox record that!"? So can I record my gaming clips?; and how?