Backend: reason: unable to verify the first certificate [backend/crmdata.jsw, postToWebhook] called with (null)

So when I try to make a post request to my server, I get the error: “reason: unable to verify the first certificate
[backend/crmdata.jsw, postToWebhook] called with (null)” . I tried both Comodo and a Godaddy cert. We are running a nginx server on the otherside. Can POST via Postman. Can Post if the browser does it. Cannot post if Wix Backend Does it. Any ideas?

Here is the backend js:

// In your site's Backend (e.g., backend/data.js)
import {fetch} from 'wix-fetch'; 

export function postToWebhook(data) {
    return fetch("URL REDACTED FOR SECURITY", {
        "method": "post",
        "headers": {
            "Content-Type": "application/x-www-form-urlencoded"
        },
        "body": data
    }).then(response => response.json());
}

Wix doesn’t currently support third party certificates (Comodo, Godaddy). It sounds like the nginx server is expecting a certificate and rejecting what Wix sends.

It may not be your issue but for cross origin requests like this you’ll need to set the mode option for fetch to "cors".

Also just to confirm is the URL being fetched with https?