AWS LexV2 messenger channel integration not sending requestAttributes - amazon-web-services

Question

I am building a AWS LexV2 chat bot that I want to integrate with Facebook Messenger via Channel Integration provided by LexV2. I am also using Lambda codehook to validate my inputs and fulfil my intents.
Following the docs, everything works as expected, except for one thing. When I log the event in my lambda function, requestAttributes field is missing from the object
My lambda function code:
import logging
logger = logging.getLogger()
logger.setLevel(logging.DEBUG)
def lambda_handler(event, context):
logger.error(event)
return ...
When I send a message to my app/page on facebook, this is what is logged:
{
"sessionId": "session-id",
"inputTranscript": "Intent utterance",
"interpretations":
[
{
"intent":
{
"slots":
{
"slot1": null,
"slot2": null
},
"confirmationState": "null",
"name": "IntentName",
"state": "InProgress"
},
"nluConfidence": 1.0
},
{
"intent":
{
"slots":
{},
"confirmationState": "null",
"name": "FallbackIntent",
"state": "InProgress"
}
}
],
"responseContentType": "text/plain; charset=utf-8",
"invocationSource": "DialogCodeHook",
"messageVersion": "1.0",
"sessionState":
{
"intent":
{
"slots":
{
"slot1": null,
"slot2": null
},
"confirmationState": "null",
"name": "IntentName",
"state": "InProgress"
},
"originatingRequestId": "req-id"
},
"bot":
{
"aliasId": "ALIASID",
"aliasName": "AliasName",
"name": "BotName",
"version": "DRAFT",
"localeId": "en_US",
"id": "bot-id"
},
"inputMode": "Text"
}
As you can see, no requestAttributes.
What's weird to me is that when I do the same thing for LexV1 bot (same facebook page/messenger app), I get these fields, e.g.
{
"requestAttributes":
{
"x-amz-lex:facebook-page-id": "page-id",
"x-amz-lex:channel-id": "channel-id",
"x-amz-lex:webhook-endpoint-url": "webhook-endpoint",
"x-amz-lex:accept-content-types": "PlainText",
"x-amz-lex:user-id": "user-id",
"x-amz-lex:channel-name": "channel-name",
"x-amz-lex:channel-type": "Facebook"
}
}
If anyone has any tips (other than "switch to V1") I would be very grateful. Thanks :))
Notes:
Changed Python Nones to nulls to easier format JSON
Replaced IDs and names from the logs with generic-id-slash-names