How to get token in ios facebook sdk?

Question

Facebook

For several days I have been trying to implement authorization through Facebook in the application.
I can’t get the user’s access_token and, accordingly, his profile information (first name, last name, etc.).
Here is an example of a custom button code taken from the Facebook documentation:

FBSDKLoginManager *login = [[FBSDKLoginManager alloc] init];
    [login
     logInWithReadPermissions: @[@"public_profile"]
     fromViewController:self
     handler:^(FBSDKLoginManagerLoginResult *result, NSError *error) {
         NSLog(@"Result: %@", [result token]);
     }];

As a result null is returned.
How do you still get the token and profile information? Maybe I'm doing something wrong?