Fatal Error On Home Page Of Enfold 2017 After Importing Demo.

Hi,
I am on the latest theme version using a child them, php version 7.3 and wordpress 5.6.2. I went and downloaded the demo for enfold 2017 as I wanted to use the home page for my site. My site is in staging and I have replaced the old theme with enfold. Everything is fine except the demo home page with the layer slider error below:

Fatal error: Uncaught Error: [] operator not supported for strings in /home/customer/www/staging1.cosmeticlaserwarehouse.com/public_html/wp-content/plugins/LayerSlider/includes/slider_markup_init.php:86 Stack trace: #0 /home/customer/www/staging1.cosmeticlaserwarehouse.com/public_html/wp-content/plugins/LayerSlider/wp/shortcodes.php(36): include() #1 /home/customer/www/staging1.cosmeticlaserwarehouse.com/public_html/wp-content/themes/enfold/config-templatebuilder/avia-shortcodes/slideshow_layerslider/slideshow_layerslider.php(191): layerslider_init(Array) #2 /home/customer/www/staging1.cosmeticlaserwarehouse.com/public_html/wp-content/themes/enfold/config-templatebuilder/avia-template-builder/php/shortcode-template.class.php(1130): avia_sc_layerslider->shortcode_handler(Array, ”, ‘av_layerslider’, Array) #3 /home/customer/www/staging1.cosmeticlaserwarehouse.com/public_html/wp-includes/shortcodes.php(343): aviaShortcodeTemplate->shortcode_handler_prepare(Array, ”, ‘av_layerslider’) #4 [internal function]: do_shortcode_ta in /home/customer/www/staging1.cosmeticlaserwarehouse.com/public_html/wp-content/plugins/LayerSlider/includes/slider_markup_init.php on line 86

Please advise how to fix. Thank you!