Jquery Ajax Post On AWS Instance Not Working

I've ran into an incredibly weird problem that I'm not entirely sure how to debug. I wrote a POST function here that works perfectly fine locally and then breaks when deployed to AWS.

     $.ajax({
            url: upload_url,
            type: 'POST',
            data: {'blobs': JSON.stringify(Blobs)},
            success: function(data){}});

Any ideas as to why post requests are not being called? I've console.log'd inside the AJAX call, and I see the log locally... but not on AWS. The code is identical.