GCP Cloud Function for Slash command not working - node.js

Question

so i'm trying to make an slash command on my slack using nodejs and Cloud Functions. I'm getting error 403 when the slash command goes out to the function, but i'm having problems to identify why it's giving me the error.
The code of the function is this:
const { WebClient } = require('#slack/web-api');
exports.slashCommand = (req, res) => {
// Verify that the request is coming from Slack
if (!req.body.token || req.body.token !== process.env.SLACK_TOKEN) {
res.status(403).end();
return;
}
// Parse the request body and extract the Slack user ID, command text, and response URL
const { user_id, text, response_url } = req.body;
// Use the Slack Web API client to post a message to the response URL
const web = new WebClient();
web.chat.postMessage({
channel: user_id,
blocks: [
{
type: 'section',
text: {
type: 'plain_text',
text: 'This is a section block'
}
},
{
type: 'divider'
},
{
type: 'section',
fields: [
{
type: 'plain_text',
text: 'This is a field'
},
{
type: 'plain_text',
text: 'This is another field'
}
]
}
]
});
// Send a 200 OK response to acknowledge receipt of the request
res.status(200).end();
};
I'm using nodeJS 18 to build
I also created gen 1 and gen2 with the same code, but the problem persists. I've given permission to allUsers to call the URL, but still no go. My SLACK_TOKEN is configured in the env. I'm suspecting that's something in the payload but i'm not understanding why this is happening. ( i'm new to this, so i'm sorry for the lack of details, if theres something i should add, let me know ).
Tried to give permission to allUsers, and still getting error. I'm really struggling to make slack validate the payload so my guess is the code checking if the payload and the token is valid is breaking everything.