Hoi.
In general, your Joomla, Template and SPPB 5.x uses Font Awesome 6 Free (!), not FA 5.
Check yourself:
media/system/css/joomla-fontawesome.min.css
components/com_sppagebuilder/assets/css/font-awesome-6.min.css
CSS Code that you used was not the perfect one, in FontAwesome documenation all is described.
And to be honest is not needed anymore.
.fa-ticket-alt {
font-family: "Font Awesome 5 Free" !important;
}
Delete it, and you will see that ticket icon still will be displayed. It means, no bug. Here is my test.
