import requests

    def fetch_customer_data(api_url, customer_id):
        headers = {
            'Authorization': 'Bearer your_api_token',
            'Accept': 'application/json'
        }
        
        try:
            response = requests.get(f"{api_url}/customers/{customer_id}", headers=headers)
            response.raise_for_status()  # Raises an HTTPError for bad responses
    
            # Process the response if successful
            data = response.json()
            print("Customer Data Retrieved Successfully:")
            print(data)
    
        except requests.exceptions.HTTPError as errh:
            print("An HTTP error occurred:", errh)
        except requests.exceptions.ConnectionError as errc:
            print("An Error Connecting to the API occurred:", errc)
        except requests.exceptions.Timeout as errt:
            print("A Timeout Error occurred:", errt)
        except requests.exceptions.RequestException as err:
            print("An Unknown Error occurred", err)
    
    # Example usage
    fetch_customer_data("https://api.example.com", "123456")