Error 500 when using the API

Hi everyone,

I’m trying to use the SuiteCRM API but I’m getting an error with HTTP code 500.

I created a new instance on AWS EC2 using bitnami, It’s a clean installation with no data, just the admin user.
I followed all steps from this tutorial: https://docs.suitecrm.com/developer/api/version-8/json-api/#_before_you_start_calling_endpoints

In addition, I created an Oauth2 client on the admin site.

Then, I’m using Postman to get an access_token this way:

POST https://<my_site>/Api/access_token

{
   "grant_type":  "client_credentials",
   "client_id": "<my_client_id>",
   "client_secret": "<my_client_secret>"
}

But I’m getting the error,
I don’t see any error on suitecrm.log.
Am I missing something?

Thanks!