Errors array before the shopping cart

Hi,
After some research on one page checkout plugins, I just installed this one and it looks like doing exactly what I need. Will definitely get the paid version to add some custom labels. However while the plugin is working, I’m getting an array of following errors on top of the checkout page. We need to resolve this before I can deploy the plugin. Could you please take a look?
I disable the plugin so far.

Best regards,
Alex

Notice: Trying to access array offset on value of type bool in /home3/astralex/public_html/tropicsathome.com/wordpress/wp-content/plugins/custom-checkout-layouts-for-woocommerce/WooCommerce/checkout/form-checkout.php on line 28

Notice: Trying to access array offset on value of type null in /home3/astralex/public_html/tropicsathome.com/wordpress/wp-content/plugins/custom-checkout-layouts-for-woocommerce/WooCommerce/checkout/form-checkout.php on line 28

Notice: Trying to access array offset on value of type bool in /home3/astralex/public_html/tropicsathome.com/wordpress/wp-content/plugins/custom-checkout-layouts-for-woocommerce/WooCommerce/checkout/form-checkout.php on line 29

Notice: Trying to access array offset on value of type null in /home3/astralex/public_html/tropicsathome.com/wordpress/wp-content/plugins/custom-checkout-layouts-for-woocommerce/WooCommerce/checkout/form-checkout.php on line 29

Notice: Trying to access array offset on value of type bool in /home3/astralex/public_html/tropicsathome.com/wordpress/wp-content/plugins/custom-checkout-layouts-for-woocommerce/WooCommerce/checkout/form-checkout.php on line 30

Notice: Trying to access array offset on value of type null in /home3/astralex/public_html/tropicsathome.com/wordpress/wp-content/plugins/custom-checkout-layouts-for-woocommerce/WooCommerce/checkout/form-checkout.php on line 30

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