Issues with startAt in orderBy timestamp - Firebase REST API - firebase

Question

Im using the Firebase REST API to retrieve data with the GET method, this is the URL im executing:
const url = `https://firestore.googleapis.com/v1/projects/${projectId}/databases/${dataBase}/documents/${collectionName}/${documentId}?&key=${apiKey}&pageSize=${pageSize}&pageToken=${nextPageToken}&orderBy=timestamp&startAt=${startTime}`;
But it return this error:
{
"error": {
"code": 400,
"message": "Invalid JSON payload received. Unknown name \"startAt\": Cannot bind query parameter. Field 'startAt' could not be found in request message.",
"status": "INVALID_ARGUMENT",
"details": [
{
"#type": "type.googleapis.com/google.rpc.BadRequest",
"fieldViolations": [
{
"description": "Invalid JSON payload received. Unknown name \"startAt\": Cannot bind query parameter. Field 'startAt' could not be found in request message."
}
]
}
]
}
}
If im omitting the paramemeter of startAt it works fine.
The format of startTime, id try it in all the following ways, and all return the same error:
Firebase return format: 2022-06-16T15:46:46.061Z
Unix Timestamp:1655394406
ISO 8601 date: 2022-06-16T15:46:46+00:00
What im doing wrong?
(For reference here is the official documentation where the startAt is explained)

Answer 1

You're calling the Firestore REST API, but are referencing the documentation for the REST API of the Realtime Database. While both products are part of Firebase, they are complete separate - and the API of one cannot be applied to the other.
For the documentation of the Firestore REST API, see https://firebase.google.com/docs/firestore/reference/rest