What is required to make a successful POST ajax call from Proxy App to Backend Service?

Technical Q&A
1

I have not found a solution or discussion about this on the forum, and I want to know how developers are making http post requests (not the shopify API) from their proxy application to their backend/internal api services. I have attempted to pass the proxy app’s access token in the header, antiforgerytoken, etc.. and I keep getting a 400 Bad Request.

I’m using .NET Razor pages for my apps so its expected to do a general setup such as:

     $.ajax({
         type: 'POST',
         url: '?handler=UpdateCollectorInfo',
         headers: {
            
             'Content-Type': 'application/json'
         },
         data: JSON.stringify(formData),
         headers: {
             'RequestVerificationToken': antiForgeryToken
         },
         success: function (response) {
       
         },
         error: function (xhr, status, error) {
           
            
         }
     });

This setup works for only my http GET requests so far. Anyone know how to resolve this?