Errors on every single product page

The errors below appear on every product’s single product page. Note that I cannot find any way to access the settings for this plugin, might be related.

Notice: Undefined index: custom_fbsharelike_enabled in /Applications/MAMP/htdocs.mysite/wp-content/plugins/woocommerce-facebook-share-like-button/tsang_fbsharelike.php on line 193

Notice: Undefined index: custom_show_only_like in /Applications/MAMP/htdocs.mysite/wp-content/plugins/woocommerce-facebook-share-like-button/tsang_fbsharelike.php on line 194

Notice: Undefined index: custom_facebook_width in /Applications/MAMP/htdocs.mysite/wp-content/plugins/woocommerce-facebook-share-like-button/tsang_fbsharelike.php on line 196

Notice: Undefined index: custom_like_verb in /Applications/MAMP/htdocs.mysite/wp-content/plugins/woocommerce-facebook-share-like-button/tsang_fbsharelike.php on line 197

Notice: Undefined index: custom_color_scheme in /Applications/MAMP/htdocs.mysite/wp-content/plugins/woocommerce-facebook-share-like-button/tsang_fbsharelike.php on line 198

Notice: Undefined index: custom_button_align in /Applications/MAMP/htdocs.mysite/wp-content/plugins/woocommerce-facebook-share-like-button/tsang_fbsharelike.php on line 199

Notice: Undefined index: custom_font in /Applications/MAMP/htdocs.mysite/wp-content/plugins/woocommerce-facebook-share-like-button/tsang_fbsharelike.php on line 200

https://wordpress.org/plugins/woocommerce-facebook-share-like-button/