Error occurs when entering prices

I installed your plugin, added 2 groups then went to change the prices for both groups, leaving the Regular Price field empty (single product) but when I click on update, I receive the below error message. It has also completely removed the price of the product even though the changes didn’t save – see here https://dev.embalmskincare.com.au/product/rosehip-oil/ – Could you please advise what I’m doing wrong? Thank you in advance! Regards, Mel

Warning: stripslashes() expects parameter 1 to be string, array given in /home/embalmsk/public_html/staging/wp-content/plugins/woocomerce-price-by-country/woocommerce-price-by-country.php on line 672

Warning: stripslashes() expects parameter 1 to be string, array given in /home/embalmsk/public_html/staging/wp-content/plugins/woocomerce-price-by-country/woocommerce-price-by-country.php on line 673

Warning: stripslashes() expects parameter 1 to be string, array given in /home/embalmsk/public_html/staging/wp-content/plugins/woocomerce-price-by-country/woocommerce-price-by-country.php on line 672

Warning: stripslashes() expects parameter 1 to be string, array given in /home/embalmsk/public_html/staging/wp-content/plugins/woocomerce-price-by-country/woocommerce-price-by-country.php on line 673

Warning: Cannot modify header information – headers already sent by (output started at /home/embalmsk/public_html/staging/wp-content/plugins/woocomerce-price-by-country/woocommerce-price-by-country.php:672) in /home/embalmsk/public_html/staging/wp-admin/post.php on line 236

Warning: Cannot modify header information – headers already sent by (output started at /home/embalmsk/public_html/staging/wp-content/plugins/woocomerce-price-by-country/woocommerce-price-by-country.php:672) in /home/embalmsk/public_html/staging/wp-includes/pluggable.php on line 1196

https://www.ads-software.com/plugins/woocomerce-price-by-country/