Keep getting unsupported_grant_type

I am trying to get user access token, i did created my own html page on the redirect url.
When i get the code i pass it to cloud code (Sashido/Parse) and i will call post from there, but i keep getting unsupported_grant_type.
I tested it on PostMan and everythings works perfectly, so i guess it’s something related to cloud and/or Sashido server.

I did a lot of try, the code i am going to show is not my first attempt.
Just a small note, i am a c++ programmer not really used to program in nodejs, so be friendly with me :slight_smile:

let patreonCheck = {
			code: patreonCode,
			grant_type: 'authorization_code',
			client_id: 'MY_CLIENT',
			client_secret: 'MY_SECRET',
			redirect_uri: ''

		const patreonRequest = await fetch('', {
			method: 'POST',
			body: JSON.stringify(patreonCheck),
			headers: { 
				'Accept': '*/*',
				'Content-Type': 'application/json',
				'Connection': 'keep-alive',
				'User-Agent': ua

Can you help me to understand what can i do to fix this issue?

You will need to debug your call step by step it seems. You can use WP plugin’s calls and match them with yours to see where it is going wrong: