Lot of errors in error.log

Hello,
here is paste from my site with lot of errors from smart cod. Can you help get rid of errors?

thrown in /home/vidamhr/public_html/wp-content/plugins/wc-smart-cod/public/class-wc-smart-cod-public.php on line 268
[09-Sep-2022 21:05:59 UTC] PHP Warning:  Undefined array key ".woocommerce-checkout-payment" in /home/vidamhr/public_html/wp-content/plugins/wc-smart-cod/public/class-wc-smart-cod-public.php on line 268
[09-Sep-2022 21:05:59 UTC] PHP Fatal error:  Uncaught ValueError: DOMDocument::loadHTML(): Argument #1 ($source) must not be empty in /home/vidamhr/public_html/wp-content/plugins/wc-smart-cod/public/class-wc-smart-cod-public.php:268
Stack trace:
#0 /home/vidamhr/public_html/wp-content/plugins/wc-smart-cod/public/class-wc-smart-cod-public.php(268): DOMDocument->loadHTML()
#1 /home/vidamhr/public_html/wp-includes/class-wp-hook.php(307): Wc_Smart_Cod_Public->apply_custom_message()
#2 /home/vidamhr/public_html/wp-includes/plugin.php(191): WP_Hook->apply_filters()
#3 /home/vidamhr/public_html/wp-content/plugins/woocommerce/includes/class-wc-ajax.php(277): apply_filters()
#4 /home/vidamhr/public_html/wp-content/plugins/woocommerce/includes/class-wc-ajax.php(293): WC_AJAX::update_order_review_expired()
#5 /home/vidamhr/public_html/wp-includes/class-wp-hook.php(307): WC_AJAX::update_order_review()
#6 /home/vidamhr/public_html/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters()
#7 /home/vidamhr/public_html/wp-includes/plugin.php(476): WP_Hook->do_action()
#8 /home/vidamhr/public_html/wp-content/plugins/woocommerce/includes/class-wc-ajax.php(90): do_action()
#9 /home/vidamhr/public_html/wp-includes/class-wp-hook.php(307): WC_AJAX::do_wc_ajax()
#10 /home/vidamhr/public_html/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters()
#11 /home/vidamhr/public_html/wp-includes/plugin.php(476): WP_Hook->do_action()
#12 /home/vidamhr/public_html/wp-includes/template-loader.php(13): do_action()
#13 /home/vidamhr/public_html/wp-blog-header.php(19): require_once('/home/vidamhr/p...')
#14 /home/vidamhr/public_html/index.php(17): require('/home/vidamhr/p...')
#15 {main}
  thrown in /home/vidamhr/public_html/wp-content/plugins/wc-smart-cod/public/class-wc-smart-cod-public.php on line 268
[09-Sep-2022 21:15:51 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:15:51 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:15:51 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:15:51 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:15:51 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:15:51 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:16:30 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:16:30 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:16:30 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:16:30 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:16:30 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338
[09-Sep-2022 21:16:30 UTC] PHP Warning:  Attempt to read property "post_type" on null in /home/vidamhr/public_html/wp-includes/class-wp-query.php on line 4338

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