No, it is not possible to fetch the user’s latitude and longitude after the app has been manually terminated by the user (i.e., the user swipes the app away from the app switcher). This is a strict limitation imposed by iOS for privacy and security reasons.
Check the link :- Apple Developer Documentation
On iOS, an app is in use when it’s in the foreground and for a short time when it transitions from the foreground to the background. If you enable background location updates, an app with When in Use authorization continues to run in the background when location services are active; if location services aren’t running, the normal suspension rules apply. If the system terminates the app or the app isn’t running, the system doesn’t launch an app with When in Use authorization to deliver new updates; it does launch an app with Always authorization for some types of location updates