Regular in-stock products crash with this plugin

I run a regular WOO site on WP 6.1.1

When I activated your plugin (which worked PERFECTLY on product pages set to “backorder”), the regular products crashed when you’d click on them like this:

In /home/u803684224/domains/surfsupwarehouse.com.au/public_html/wp-content/plugins/backorder-custom-description/backorder-custom-description.php on line 104

Call stack:

bocustom_custom_action_after_single_product_title()
wp-includes/class-wp-hook.php:308
WP_Hook::apply_filters()
wp-includes/plugin.php:205
apply_filters()
wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-product.php:2119
WC_Product::get_availability_text()
wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-product.php:2095
WC_Product::get_availability()
wp-content/plugins/woocommerce/includes/wc-template-functions.php:3543
wc_get_stock_html()
wp-content/plugins/woocommerce/includes/class-wc-product-variable.php:367
WC_Product_Variable::get_available_variation()
wp-content/plugins/woocommerce/includes/class-wc-product-variable.php:312
WC_Product_Variable::get_available_variations()
wp-content/plugins/woocommerce-gateway-stripe/includes/payment-methods/class-wc-stripe-payment-request.php:905
WC_Stripe_Payment_Request::should_show_payment_request_button()
wp-content/plugins/woocommerce-gateway-stripe/includes/payment-methods/class-wc-stripe-payment-request.php:757
WC_Stripe_Payment_Request::scripts()
wp-includes/class-wp-hook.php:308
WP_Hook::apply_filters()
wp-includes/class-wp-hook.php:332
WP_Hook::do_action()
wp-includes/plugin.php:517
do_action()
wp-includes/script-loader.php:2180
wp_enqueue_scripts()
wp-includes/class-wp-hook.php:308
WP_Hook::apply_filters()
wp-includes/class-wp-hook.php:332
WP_Hook::do_action()
wp-includes/plugin.php:517
do_action()
wp-includes/general-template.php:3043
wp_head()
wp-content/themes/ssw/header.php:8
require_once()
wp-includes/template.php:783
load_template()
wp-includes/template.php:718
locate_template()
wp-includes/general-template.php:48
get_header()
wp-content/themes/ssw/woocommerce/single-product.php:7
include()
wp-includes/template-loader.php:106
require_once()
wp-blog-header.php:19
require()
index.php:17

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