500 Error with Affiliate

-- HikaShop version -- : 6.1.1
-- Joomla version -- : 5.4.1
-- PHP version -- : 8.2.30
-- Browser(s) name and version -- : Any
-- Error-message(debug-mod must be tuned on) -- : hikashop error 0 call to undefined function empty () plugins/system/hikashopaffiliate/hikashopaffiliate.php:269

Took a bit to figure out why only some customers were experiencing checkout issues (500 error).

It happens only when an affiliate is assigned to the customer's account.

Once we turned on Joomla debug and used a customer with an affiliate (other than themselves) we saw this:

hikashop error 0 call to undefined function empty () plugins/system/hikashopaffiliate/hikashopaffiliate.php:269

if(!emtpy($user->user_params->affiliation_category_restriction)) {

if (!empty($user->user_params->affiliation_category_restriction)) {