NSUserDefaults data is lost after enabling app groups.

I have created the user defaults with suite Name like below without enabling app groups in the Signing & capabilities. 

Code Block  
NSUserDefaults *defaults = [[NSUserDefaults alloc] initWithSuiteName:@"group.com.mycompanyname.share"];
  // Storing the value here 
  [defaults setValue:@"This is value1" forKey:@"key1"];
  [defaults synchronize];
 // Retrieving value here for key1
  NSString *value = [defaults valueForKey:@"key1"];
  NSLog(@"This data stored for key1 is : %@", value);

The data is stored successfully and got the logs while retrieving key1: 

Code Block 
2021-05-14 16:35:34.031941+0530 demo[16478:224183] This data stored for key1 is : This is value1

So everything is good till now.

Now comes the problem where I enable the app groups for my project in Signing & capabilities selected the name group.com.mycompanyname.share and reinstalled the app 

When I tried to get the stored value using the below code the data user defaults data is lost getting null:
 

Code Block 
NSUserDefaults *defaults = [[NSUserDefaults alloc] initWithSuiteName:@"group.com.mycompanyname.share"];
 // Retrieving value here for key1
NSString *value = [defaults valueForKey:@"key1"];
NSLog(@"This data stored for key1 is : %@", value);

Got the logs like this (null) data for key1 :

Code Block 
2021-05-14 16:36:24.174784+0530 demo[16512:225476] This data stored for key1 is : (null)

Please help me on this how to fix this issue?