How to fix the net::ERR_CONNECTION_CLOSED error when making a GET request?

Question

JavaScript

Good afternoon. When executed, an error occurs and the request does not even go to the server. Could the problem be due to a long GET request body exceeding 2048 characters? How can this be bypassed?

$.ajax({
            url: 'https://api.cdek.ru/calculator/calculate_price_by_jsonp.php',
            data: {
              "json": formDataJson
            },
            type: 'GET',
            dataType: "jsonp",            
            success: function(data) {}
})