> ## Documentation Index
> Fetch the complete documentation index at: https://docs.invoca.com/llms.txt
> Use this file to discover all available pages before exploring further.

# "Call Must Be Present" Error on the Signal API

> This error occurs when the Signal API receives a transaction ID for a call that hasn't finished importing into Invoca yet.

**Applies to:** Signal API

## Symptoms

A request to the Signal API returns a 403 Forbidden response similar to:

```json theme={null}
{
  "statusCode": 403,
  "status": "Forbidden",
  "body": "{\"errors\":{\"class\":\"InvalidInput\",\"invalid_data\":\"Call must be present\"}}"
}
```

## Cause

The request references a transaction ID that doesn't exist in Invoca yet. This happens when the API request is sent before the call has finished importing into Invoca — a race condition between the request and the import process.

## Resolution

Try one of the following:

1. Delay your request slightly to allow the call to finish importing before you reference its transaction ID.
2. Pass the `call_in_progress` parameter as `true` if you don't need the response Invoca normally provides for a completed call.

If you're not sure how much delay to build in, compare the timing of when your calls typically finish importing against when your API requests are sent.

## Where to go next

* [Can I Apply Signals or Marketing Data to Multiple Calls Using the Signal API?](/s/article/apply-signals-marketing-data-multiple-calls-signal-api)
* [Can I Modify a Call Record Before the Call Ends?](/s/article/modify-call-record-before-call-ends)