Zoom appssdk Authorization ({"reason":"Invalid authorization code","error":"invalid_grant"})

Hello, I am currently working on a WebApp in React, in which I am using the "@zoom/appssdk: "^0.16.34", and with that I am using the zoomSdk to handle the seamless authentication process when the user is inside the Zoom client.

These are the auth steps on the WebApp

await zoomSdk.config({ capabilities: ["authorize", "onAuthorized", "openUrl"] });

const codeChallenge = generateCodeChallenge() // base64url-encoded string 43-128 characters
await zoomSdk.authorize({ codeChallenge: codeChallenge });

zoomSdk.onAuthorized((event) => {
     console.log(" zoomSdk.onAuthorized: ", event); 

     // code:  TOKEN SENT IN AUTH REQUEST
     // redirectUri:  APP REDIRECT URI
     // result: true
     // timestamp: 1758705561

     await callZoomAuthEndpointJava({token: event.code})
});

Then I call my endpoint which will will go to https://zoom.us/oauth/token to get an access token so that I can later go to https://api.zoom.us/v2/users/me and fetch the user’s information

And these are the steps:

URL-> https://zoom.us/oauth/token?code=TOKEN&grant_type=authorization_code
Headers-> Base64(clientId + ":" + secretId)

But when i make this request I get this error: {“reason”:“Invalid authorization code”,“error”:“invalid_grant”}. I had this working until May 2025, but now I think something has changed in the oauth/token request because I can no longer get new tokens.

Has something changed in the Apps SDK in which I need to send anything else more than the code from the onAuthorizedmethod for the Zoom token endpoint, or what is the issue?

Thanks in advance!