There are only 3 reason why your Screen Time would turn the Camera off where it would be removed from your Home Screen.
- You are a member of a Family Sharing plan where the Organizer can make that change. Remove yourself from the Family Sharing plan or communicate with the Organizer so that does not happen.
or
- Someone else knows the Passcode to your device and can make that change with physical access to your device. Changing the Passcode would resolve that problem.
or
- You have Share Across Devices turned on at Settings > Screen Time > Share Across Devices and there is another device that uses your Apple Account. You can easily tell if there is another device that uses your Apple Account by going to Settings > [name on top], and scroll to the bottom to see the list of devices signed into your Apple Account. You can either remove that device by tapping on it and follow up by changing your Apple Account Password to prevent them from signing in again, or for known devices sharing your Apple Account, just turn off Share Across Devices.
Now you just need to figure out which one of the 3 it is and take those steps to prevent it from happening again.
As for a bank log showing you are in another location, I have no idea what you are referring to there or where you are seeing it. Feel free to provide a screenshot as long as any personal information has been redacted.