title: CXCallObserverDelegate not being invoked
body: <p>Note: I am new to Objective C</p>
  <p>I have implemented the CXCallObserverDelegate callChanged delegate in my custom React Native module but it is not invoked when i receive a VOIP call</p>
  <p>In didFinishLaunchingWithOptions of AppDelegate</p>
  <pre><code>CallManager *manager = [CallManager new];
  [manager someMethod:@&quot;Hoola&quot;]; // sending a test string to print
  </code></pre>
  <p>In CallManager.m</p>
  <pre><code>#import &quot;CallManager.h&quot;
  #import &quot;RNCallKeep.h&quot;
  
  @implementation CallManager
  
  RCT_EXPORT_MODULE();
  
  -(void)someMethod: (NSString *)someString
  {
    
    NSLog(@&quot;Hello world callObserver %@&quot;, someString); // Hoola string gets printed here means this method is working
  
    CXCallObserver *callObserver = [[CXCallObserver alloc] init];
    self.callObserver = callObserver;
    [callObserver setDelegate:(id)self queue:nil]; 
  
  }
  
  -(void)callObserver:(CXCallObserver *)callObserver callChanged:(CXCall *)call {
    NSLog(@&quot;Hello world callObserver&quot;); // this doesnt get printed when call is received or status changes
  }
  
  @end
  </code></pre>
  <p>In my CallManager.h file</p>
  <pre><code>#import &lt;Foundation/Foundation.h&gt;
  #import &lt;React/RCTBridgeModule.h&gt;
  #import &lt;CallKit/CallKit.h&gt;
  
  
  NS_ASSUME_NONNULL_BEGIN
  
  @interface CallManager : NSObject&lt;RCTBridgeModule, CXCallObserverDelegate&gt;
  
  @property (atomic, strong) CXCallObserver *callObserver;
  - (void)someMethod: (NSString *)someString;
  
  @end
  
  NS_ASSUME_NONNULL_END
  </code></pre>
  <p>App is compiling fine and launching and performing all things but when I receive a VOIP call and CallKIT UI is invoked, i don't get call status changed events on accept or reject. Note that NSLogs are printed correctly, i put them there for debug and they are working.</p>