Process completed with exit code 1.

Cannot convert null literal to non-nullable reference type.

Nullability of reference types in type of 'event PropertyChangedEventHandler DeviceConfig.PropertyChanged' doesn't match implicitly implemented member 'event PropertyChangedEventHandler? INotifyPropertyChanged.PropertyChanged'.

Cannot convert null literal to non-nullable reference type.

Nullability of reference types in type of parameter 'value' of 'object EnumToBoolConverter.Convert(object value, Type targetType, object parameter, CultureInfo culture)' doesn't match implicitly implemented member 'object? IValueConverter.Convert(object? value, Type targetType, object? parameter, CultureInfo culture)' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'parameter' of 'object EnumToBoolConverter.Convert(object value, Type targetType, object parameter, CultureInfo culture)' doesn't match implicitly implemented member 'object? IValueConverter.Convert(object? value, Type targetType, object? parameter, CultureInfo culture)' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'value' of 'object EnumToBoolConverter.ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)' doesn't match implicitly implemented member 'object? IValueConverter.ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'parameter' of 'object EnumToBoolConverter.ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)' doesn't match implicitly implemented member 'object? IValueConverter.ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)' (possibly because of nullability attributes).

Method, operator, or accessor 'INetworkCommands.Ping(DeviceConfig)' is marked external and has no attributes on it. Consider adding a DllImport attribute to specify the external implementation.

Because this call is not awaited, execution of the current method continues before the call is completed. Consider applying the 'await' operator to the result of the call.