Hey there BenGST,
Do you use an accessory with your iPhone X when trying to record your gift swing? If yes, does temporarily removing that accessory help stop this unexpected zoom happening in your videos?
We're asking this as the camera should only be zooming in on an iPhone X by either pinching to zoom in or using the toggles, as seen below:
"Zoom in or out
- On all models, open Camera and pinch the screen to zoom in or out.
- On iPhone models with Dual and Triple camera systems, toggle between 0.5x, 1x, 2x, 2.5x, and 3x to quickly zoom in or out (depending on your model). For a more precise zoom, touch and hold the zoom controls, then drag the slider right or left."
That information, and more, can be seen here: iPhone camera basics - Apple Support
Also, if you haven't already, you can see if restarting may help: Restart your iPhone - Apple Support Restarting can refresh the iOS and resolved unexpected issues.
Take care.