Hello SwipeBar,
After reviewing your post, it sounds like you are not able to swipe up from the bottom of the screen on the iPhone.
Are you using a specific app when this happens?
Is the iPhone horizontal or vertical when this happens?
Are you able to close apps?
"To go to the Home screen at any time, swipe up from the bottom edge of the screen."
Use gestures to navigate your iPhone X and later
"On an iPhone X or later, or an iPad with iOS 12 or later, or iPadOS, from the Home screen, swipe up from the bottom of the screen and pause slightly in the middle of the screen. "
How to force an app to close on your iPhone, iPad, or iPod touch
Please don't hesitate to let us know if the steps resolved your issue or if you need additional assistance.
Thank you for using Apple Support Communities. Have a nice day.