Flutter camera doesn't open in real device

Question

I'm trying to take a picture using the package image_picker: ^0.6.1 and I have the following code:

if (camera)
  tempStore = await ImagePicker.pickImage(source: ImageSource.camera);
else
  tempStore = await ImagePicker.pickImage(source: ImageSource.gallery);

If i click on gallery the phone ask me permissions and I can take a image from gallery but if I click on camera nothing happens and in console there aren't errors.

I have tried to add this lines to android.manifest.XML

<uses-permission android:name="android.permission.CAMERA" />

<uses-feature android:name="android.hardware.camera"
    android:required="true" />

But it doesn't work anyway.

I have Flutter in version v1.7.8+hotfix.3. I don't know why in simulator it works but in real phone it doesn't.

What could be the problem?