Why is my Firebase Admin SDK in Node.js returning ACCESS_TOKEN_EXPIRED with a new service account key?

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Up until recently I was able to run queries with the Firebase SDK using Node.js without any issues. Now, however, despite creating a new JSON key (which shows no expiration in Firebase settings), I keep receiving an ACCESS_TOKEN_EXPIRED error.

In my Firebase settings it shows:

I created my key in JSON format and initialized it in Node.js as instructed:

JAVASCRIPTCopied
var admin = require("firebase-admin");

const serviceAccount = require('pathtomykey.json'); 

admin.initializeApp({
    credential: admin.credential.cert(serviceAccount),
    databaseURL: "https://projectid-default-rtdb.firebaseio.com"
});

Yet, I continue to get the following error:

PLAINTEXTCopied
node:internal/process/promises:288
            triggerUncaughtException(err, true /* fromPromise */);
            ^
Error: 16 UNAUTHENTICATED: Request had invalid authentication credentials. Expected OAuth 2 access token, login cookie or other valid authentication credential. See https://developers.google.com/identity/sign-in/web/devconsole-project.
     {
  code: 16,
  details: 'Request had invalid authentication credentials. Expected OAuth 2 access token, login cookie or other valid authentication credential. See https://developers.google.com/identity/sign-in/web/devconsole-project.',
  metadata: Metadata {
    internalRepr: Map(4) {
      'google.rpc.errorinfo-bin' => [
        Buffer(125) [Uint8Array] [
           10, 
          ... 25 more items
        ]
      ],
      'grpc-status-details-bin' => [
        Buffer(385) [Uint8Array] [
           
          ... 285 more items
        ]
      ],
      'www-authenticate' => [ 'Bearer realm="https://accounts.google.com/"' ],
      'x-debug-tracking-id' => [ '19025914238;o=1' ]
    },
    options: {}
  },
  statusDetails: [
    ErrorInfo {
      metadata: {
        method: 'google.firestore.v1.Firestore.RunQuery',
        service: 'firestore.googleapis.com'
      },
      reason: 'ACCESS_TOKEN_EXPIRED',
      domain: 'googleapis.com'
    }
  ],
  reason: 'ACCESS_TOKEN_EXPIRED',
  domain: 'googleapis.com',
  errorInfoMetadata: {
    method: 'google.firestore.v1.Firestore.RunQuery',
    service: 'firestore.googleapis.com'
  }
}

I have tried using both my administrator account and a service account. This setup worked until last year, and now I’m at a loss as to why the token appears expired even when the key is new. Can someone shed some light on this issue?