I've the following dataset on a real-time Firebase database:

{
    "posts": {
        "key1": {
            message: "message",
            title: "title",
            timeStamp: 1513160947658
        },
        "key2": {
            message: "message",
            title: "title",
            timeStamp: 1625904019915
        },
        "key3": {
            message: "message",
            title: "title",
            timeStamp: 1626171405405
        }
    }
}

Here is the Firebase component:

Firebase.js

import { get, getDatabase, limitToFirst, limitToLast, onValue, orderByChild, query, ref } from 'firebase/database'
import firebase from 'firebase/compat/app'
import 'firebase/compat/database'

const config = { ... }
const db = getDatabase()

firebase.initializeApp(config)

export { db, get, limitToFirst, limitToLast, onValue, orderByChild, query, ref }

A component gets the first and last post:

FirstAndLast.js

import { db, get, limitToFirst, limitToLast, orderByChild, query, ref } from './Firebase'

const fetch = async () => {

    // If I execute both lines, Listener.js snapshot.val() returns a null value 
    // If I remove one of these lines, Listener.js snapshot.val() returns the desired object
    let snapshotFirst = await get(query(ref(db, 'posts'), orderByChild('timeStamp'), limitToFirst(1)))
    let snapshotLast  = await get(query(ref(db, 'posts'), orderByChild('timeStamp'), limitToLast(1)))

}

Another component listens to the key2 branch:

Listener.js

import { db, onValue, ref } from './Firebase'

onValue(ref(db, 'posts/key2'), snapshot => {

    console.log(snapshot.val())

})

If I execute both components at the same time, Listener.js prints the desired object at first, but later on returns a null value as the final result. If I remove (or comment) one of the snapshots at FirstAndLast.js, there aren't any issues.

It's anything wrong in combining limitToFirst() and limitToLast()?