Hi,
It could be that those users don't have separate billing and shipping addresses ?
A few versions ago of HikaShop, we added an address_type to the addresses so that shipping addresses and billing addresses can be separated. That way, it makes more sense on the checkout for the customers, and you can also configure custom address fields based on the type of the address.
This also mean that we had to modify the export areas to handle these. But maybe some of your users still have addresses without a type and in that case the addresses can be used both for billing and shipping on the checkout, but maybe the mass action system doesn't handle them properly.
In fact, looking at the code of the mass action export, I think it's probably the issue here.
Edit the file administrator/components/com_hikashop/classes/massaction.php and change the line:
if(!count($element->shipping_address) && $address->address_type == 'shipping') {
to:
if(!count($element->shipping_address) && in_array($address->address_type, array('shipping', '', 'both'))) {
and the line:
if(!count($element->billing_address) && $address->address_type == 'billing') {
to:
if(!count($element->billing_address) && in_array($address->address_type, array('billing', '', 'both'))) {
It should then work better.
Let us know how it goes so that we can include that patch on our end.