fix message received from woocommerce

Job ID: 32423113

Budget: €8 – €30 EUR

When we use our plugin and we insert number we receive a message from woocommerce (see image attached) and client has to click OK.
Some days ago wasn't like that, this message didn't happear. We don't want this message.
Maybe the last developer forget some develop tools or something...
Related categories: PHP JavaScript WordPress HTML WooCommerce