Send a TriggerMessage after sending a CALLERROR : Security Error

I wanted to handle the case when the CP is booted and the first message it sends is not a BootNotification request. So the procedure from the CSMS side should be : Check if BootNotification is recorded before or not. I am doing this using a DB call and storing the latest BootNotification call timestamp in it. So if a new CP gets connected and it doesn't send a BootNotification first, then the value is NULL and the CSMS shall raise a SecurityError. After raising the security error, a CALLERROR is sent to the CP. And after that, I should be able to call a trigger message somehow. Can you help me find the place where should I call trigger message function? I thought of using a @after tag, but the code is unreachable.

My @on(Authorize) code

@on(Action.Authorize)
async def on_authorize(self, id_tag:str,*args, **kwargs):
  await self.check_boot_status_accepted()
  return call_result.AuthorizePayload(
      id_tag_info={
          'status': AuthorizationStatus.accepted
      }
  )

My check_boot_status_accepted() function

async def check_boot_status_accepted(self):
    if not self.boot_status == RegistrationStatus.accepted.value:
        self.trigger_message_for = MessageTrigger.boot_notification
        asyncio.create_task(self.trigger_message(MessageTrigger.boot_notification))
        raise SecurityError(description="No BootNotification received!")
    self.trigger_message_for = None
    return True

The reason why @after doesn't work: (in the charge_point.py file)

try:
    handler = handlers['_on_action']
except KeyError:
    raise NotImplementedError(f"No handler for '{msg.action}' "
                              "registered.")

try:
    response = handler(**snake_case_payload)
    if inspect.isawaitable(response):
        response = await response
except Exception as e:
    LOGGER.exception("Error while handling request '%s'", msg)
    response = msg.create_call_error(e).to_json()
    await self._send(response)

    return

CSMS log:

14:24:02,149 websockets.server INFO server listening on 0.0.0.0:9000
14:24:08,787 websockets.server INFO connection open
14:24:08,787 root INFO Protocols Matched: ocpp1.6
14:24:08,789 root INFO Charger CP_1 connected.
14:24:08,796 ocpp INFO CP_1: receive message [2,"9bd5f9e3-bc2c-47d6-a8ef-dc93883c767a","Authorize",{"idTag":"id_tag"}]
14:24:08,874 ocpp INFO CP_1: send [2,"2dca0ac9-6405-4855-a95c-e3f7059b2cdf","TriggerMessage",{"requestedMessage":"BootNotification"}]
14:24:18,814 ocpp ERROR Error while handling request '<Call - unique_id=9bd5f9e3-bc2c-47d6-a8ef-dc93883c767a, action=Authorize, payload={'idTag': 'id_tag'}>'
Traceback (most recent call last):
  File "D:\evy/dev/cms-ocpp\ocpp\charge_point.py", line 196, in _handle_call
    response = await response
  File "D:\evy/dev/cms-ocpp\csms\v16\central_system\charge_point_handler.py", line 52, in on_authorize
    await self.check_boot_status_accepted()
  File "D:\evy/dev/cms-ocpp\csms\v16\central_system\charge_point_handler.py", line 28, in check_boot_status_accepted
    raise SecurityError(description="No BootNotification received!")
ocpp.exceptions.SecurityError: SecurityError: No BootNotification received!, {}
14:24:18,858 ocpp INFO CP_1: send [4,"9bd5f9e3-bc2c-47d6-a8ef-dc93883c767a","SecurityError","No BootNotification received!",{}]
14:24:18,859 ocpp INFO CP_1: receive message [3,"2dca0ac9-6405-4855-a95c-e3f7059b2cdf",{"status":"Accepted"}]
14:24:18,861 ocpp INFO CP_1: receive message [2,"3949a5cb-40fb-4b06-9673-f00b11331500","BootNotification",{"chargePointModel":"Model-1","chargePointVendor":"Vendor-1"}]
14:24:18,870 ocpp INFO CP_1: send [3,"3949a5cb-40fb-4b06-9673-f00b11331500",{"currentTime":"2022-01-26T08:54:18.868944","interval":60,"status":"Accepted"}]
14:24:18,876 ocpp INFO CP_1: receive message [2,"4107d2a3-b40e-4799-8e21-5a02d300ce8b","Heartbeat",{}]
14:24:18,880 ocpp INFO CP_1: send [3,"4107d2a3-b40e-4799-8e21-5a02d300ce8b",{"currentTime":"2022-01-26T08:54:18.879837"}]

CP log:

14:24:08,794 ocpp INFO CP_1: send [2,"9bd5f9e3-bc2c-47d6-a8ef-dc93883c767a","Authorize",{"idTag":"id_tag"}]
14:24:08,875 ocpp INFO CP_1: receive message [2,"2dca0ac9-6405-4855-a95c-e3f7059b2cdf","TriggerMessage",{"requestedMessage":"BootNotification"}]
14:24:08,880 ocpp INFO CP_1: send [3,"2dca0ac9-6405-4855-a95c-e3f7059b2cdf",{"status":"Accepted"}]
14:24:18,859 ocpp INFO CP_1: receive message [4,"9bd5f9e3-bc2c-47d6-a8ef-dc93883c767a","SecurityError","No BootNotification received!",{}]
14:24:18,860 ocpp WARNING Received a CALLError: <CallError - unique_id=9bd5f9e3-bc2c-47d6-a8ef-dc93883c767a, error_code=SecurityError, error_description=No BootNotification received!, error_details={}>'
14:24:18,860 ocpp INFO CP_1: send [2,"3949a5cb-40fb-4b06-9673-f00b11331500","BootNotification",{"chargePointModel":"Model-1","chargePointVendor":"Vendor-1"}]
14:24:18,871 ocpp INFO CP_1: receive message [3,"3949a5cb-40fb-4b06-9673-f00b11331500",{"currentTime":"2022-01-26T08:54:18.868944","interval":60,"status":"Accepted"}]
14:24:18,875 ocpp INFO CP_1: send [2,"4107d2a3-b40e-4799-8e21-5a02d300ce8b","Heartbeat",{}]
14:24:18,881 ocpp INFO CP_1: receive message [3,"4107d2a3-b40e-4799-8e21-5a02d300ce8b",{"currentTime":"2022-01-26T08:54:18.879837"}]

mobilityhouse / ocpp

Send a TriggerMessage after sending a CALLERROR : Security Error #295