how to trust app

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Install custom enterprise apps on iOS - Apple Support

If you already have one on your phone, you'll see it beneath VPN

If you still need help, contact your employer's IT department.

If you got the profile somewhere else, delete it. It's a security risk.

Profile and Device Managements are found in iPhones supervised by organisations or enterprise who own the iPhone.

Those with personal iPhone will have profile installed only of they deal with certain apps that require updating your profile.

You need to turn off your low power mode. As this restricts the apps refresh. What app are you trying to trust?

You should ABSOLUTELY, POSITIVELY NEVER install a game app that you didn't get from the Apple app store. It is out to steal your data. If it was a legitimate app it would be in the app store.