WP Customizer Not Fully Functional

Using WP Customizer to edit my Enrollment Pro template, some items I am unable to edit.

For example: Slider Settings – Slider Type – Repeater Slider –
The demo content is there but I cannot edit it. I cannot reorder the 2 Single Slides. I cannot add a slide.

Another example: Additional Settings – Social Icons
I cannot edit existing icons, cannot reorder, and cannot Add Icon.

Any suggestions?