Beanstalk daemon in Worker environment for Python does not delete messages from SQS queue even after sending '200 OK' response

There is a beanstalk worker environ setup in Python to do some large zip extraction process. I've implemented it using the following code. Once the process is done application code is sending '200 OK' response to beanstalk but beanstalk daemon is not deleting message from the SQS where the beanstalk daemon reads messages from. The extraction process takes around 30-32 mins to complete.

SQS: Visibility timeout : 1 hr 30 mins Beanstalk: Visibility/Inactivity timeout: 5400

Code:

def application(environ, start_response):

status = "400 Bad Request"
response = "Pending"

path = environ['PATH_INFO']
method = environ['REQUEST_METHOD']

# HTTP request method is always 'POST'
if method == 'POST':
    # If 'HTTP path' is set to '/' in Elastic beanstalk configuration 
    if path == '/':
        message_body_size = int(environ['CONTENT_LENGTH'])
        message = environ['wsgi.input'].read(message_body_size)
        
        if message:
            resources = message['resources'] if 'resources' in message else ''
            if resources:
                for item in resources:
                    zip_path = item['zip_file_path'].strip() if 'zip_file_path' in item else ''
                    extract_path = item['zip_extract_destination'].strip() if 'zip_extract_destination' in item else ''
                    
                    if all([zip_path, extract_path]):
                        try:
                            with zipfile.ZipFile(zip_path, mode="r") as archive:
                                archive.extractall(extract_path)                                
                        except Exception as error:
                            process_error = True
                            process_log_message = f'Exception raised when extracting package: {zip_path} - {str(error)}'
                            break
                    else:
                        process_error = True
                        process_log_message = 'Source or destination location for input package is blank'
                        break
                        
            if process_error == True:
                write_to_log_stream(process_log_message)
            else:
                status = '200 OK'
                response = b'Done'                      
 
# Send response to Elastic Beanstalk daemon
headers = [('Content-type', 'text/plain')]
start_response(status, headers)
return [response]

Where I'm doing wrong?