TouchID popup failed to shown ontop of app UI

Hi,

I am developing an app that using TouchID (LocalAuthentication framework).

The TouchID popup dialog sometimes shown behind the application UI. My expectation is it should shown ontop of my app UI. I have noticed that this only happened on iPadOS 13 developer beta 1. I have never facing the same issue on previous iOS version.

Anyone facing the same issue?

Here's the code snippet:

    __block LAContext *laContext = [[LAContext alloc] init];
    if ([laContext canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error]) {
        [laContext evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics
                  localizedReason:@"Touch ID message here"
                            reply:^(BOOL success, NSError *authenticationError) {
                                [laContext invalidate];
                            }];
    }

Additional note:

* My test device is iPad 2018 model.