Как решить проблему с Ajax?

$.ajax({
        type: 'POST',
        headers: { "cache-control": "no-cache" },
        url: callingFile + '?rand=' + new Date().getTime() + advApiParam,
        async: false,
        cache: false,
        dataType : "json",
        data: 'ajax=true&'+params+'&token=' + static_token ,
        success: function(jsonData)
        {
          if (jsonData.hasError)
          {
            var tmp = '';
            var i = 0;
            for(var error in jsonData.errors)
              //IE6 bug fix
              if(error !== 'indexOf')
              {
                i = i+1;
                tmp += '<li>'+jsonData.errors[error]+'</li>';
              }
            tmp += '</ol>';
            var errors = '<b>'+txtThereis+' '+i+' '+txtErrors+':</b><ol>'+tmp;
            $('#opc_account_errors').slideUp('fast', function(){
              $(this).html(errors).slideDown('slow', function(){
//                              $.scrollTo('#opc_account_errors', 800);
              });
            });
          }
          else
          {
            $('#opc_account_errors').slideUp('slow', function(){
              $(this).html('');
            });
          }

          isGuest = parseInt($('#is_new_customer').val()) == 1 ? 0 : 1;
          // update addresses id
          if(jsonData.id_address_delivery !== undefined && jsonData.id_address_delivery > 0)
            $('#opc_id_address_delivery').val(jsonData.id_address_delivery);
          if(jsonData.id_address_invoice !== undefined && jsonData.id_address_invoice > 0)
            $('#opc_id_address_invoice').val(jsonData.id_address_invoice);

          if (jsonData.id_customer !== undefined && jsonData.id_customer !== 0 && jsonData.isSaved)
          {
            // update token
            static_token = jsonData.token;

            // It's not a new customer
            if ($('#opc_id_customer').val() !== '0')
              if (!saveAddress('delivery'))
                return false;

            // update id_customer
            $('#opc_id_customer').val(jsonData.id_customer);

            if ($('#invoice_address:checked').length !== 0)
            {
              if (!saveAddress('invoice'))
                return false;
            }

            // update id_customer
            $('#opc_id_customer').val(jsonData.id_customer);

            // force to refresh carrier list
            if (isGuest)
            {
              isLogged = 1;
              $('#opc_account_saved').fadeIn('slow');
              $('#submitAccount').hide();
              updateAddressSelection(advApiParam);
            }
            else
              updateNewAccountToAddressBlock(advApiParam);
          }
          $('#opc_new_account-overlay, #opc_delivery_methods-overlay, #opc_payment_methods-overlay').fadeIn('slow');
        },
        error: function(XMLHttpRequest, textStatus, errorThrown) {
          if (textStatus !== 'abort')
          {
            error = "TECHNICAL ERROR: unable to save account \n\nDetails:\nError thrown: " + XMLHttpRequest + "\n" + 'Text status: ' + textStatus;
                  if (!!$.prototype.fancybox)
                      $.fancybox.open([
                          {
                              type: 'inline',
                              autoScale: true,
                              minHeight: 30,
                              content: '<p class="fancybox-error">' + error + '</p>'
                          }
                      ], {
                          padding: 0
                      });
                  else
                      alert(error);
          }
          $('#opc_new_account-overlay, #opc_delivery_methods-overlay, #opc_payment_methods-overlay').fadeIn('slow')
        }
      });