3011 when sending messages in Instagram using external request

I am struggling to send messages to a subscribed person on instagram. I am getting the following error:

```
2025-10-14T16:58:10.921-0600    ERROR   manychat/client.go:145  ManyChat API error response     {"status_code": 400, "response_body": "{\"status\":\"error\",\"message\":\"Content can’t be sent to the subscriber without a message tag. Subscriber’s last interaction was over 0h ago (more than 24 hours ago)\",\"code\":3011}"}
```

As you can see, the subscribers last interaction was 0h ago. The account this is connected to is a business and verified account.

This is what the request is looking like:

```
{
  "subscriber_id": "xxx",
  "data": {
    "version": "v2",
    "content": {
      "messages": [
        {
          "type": "text",
          "text": "Hi there! "
        }
      ]
    }
  }
}
```
My understanding is that it doesn’t need a message tag because it’s been 0 hours since the last interaction but I have also tried with message_tags.

The flow i currently have is

“User sends message” (I have it match with “hi”) → Set instagram opt in (i have tried without this) → Make external request

The external request returns a reply, where i try to use the API to write a new message and then send it back to manychat which fails with the above error.

I have checked that my subscriber id i am using matches the one in the UI of manychat. I am at such a loss. I have no idea what else to check.

Any help or guidance would be greatly appreciated

Thanks for reading this