Get Users Web service Moodle

Hello, I'm trying to get users with this function core_user_get_users

I had the wstoken, wsfunction, moodlewsrestformat and criteria[0][key]=deleted&criteria[0][value]=0

I think the code is well, but I have problem with the time in the server, because the Browser loads 5 seconds and shows an error

The error:

{

    "exception": "invalid_response_exception",

    "errorcode": "invalidresponse",

    "message": "Detectado valor de respuesta no válido"

}

Help pls