Notice from your plugin

Hi!
I got the notice below when I use your plugin combined with my payment module (Klarna). Is that something that I need to take care of?

( ! ) Notice: Undefined index: post_type in /home/styling/web/new.stylingagenten.se/public_html/wp-content/plugins/customer-reviews-woocommerce/class-ivole-admin-coupon.php on line 902
Call Stack
# Time Memory Function Location
1 0.0012 257448 {main}( ) ../admin.php:0
2 1.2766 74724000 do_action( ) ../admin.php:156
3 1.2766 74724704 WP_Hook->do_action( ) ../plugin.php:453
4 1.2766 74724832 WP_Hook->apply_filters( ) ../class-wp-hook.php:310
5 1.2888 75144648 call_user_func_array ( ) ../class-wp-hook.php:286
6 1.2888 75145152 klarna_checkout_admin_error_notices( ) ../class-wp-hook.php:286
7 1.2889 75163712 url_to_postid( ) ../woocommerce-gateway-klarna.php:379
8 1.2900 75298304 WP_Query->__construct( ) ../rewrite.php:599
9 1.2900 75298304 WP_Query->query( ) ../class-wp-query.php:3336
10 1.2900 75300352 WP_Query->get_posts( ) ../class-wp-query.php:3230
11 1.2900 75300352 WP_Query->parse_query( ) ../class-wp-query.php:1621
12 1.2909 75313936 do_action_ref_array( ) ../class-wp-query.php:1006
13 1.2909 75314024 WP_Hook->do_action( ) ../plugin.php:515
14 1.2909 75314152 WP_Hook->apply_filters( ) ../class-wp-hook.php:310
15 1.2909 75315352 call_user_func_array ( ) ../class-wp-hook.php:286
16 1.2909 75315792 Ivole_Admin_Coupon->coupons_quick_link_filter( ) ../class-wp-hook.php:286

BR
Andreas

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