breaks with the latest version of woocommerce

After updating to the latest version of woocommerce wallee breaks the site

#WordPress-Version 5.3.2
Aktuelles Theme: Astra (Version 2.2.1)
Aktuelles Plugin: WooCommerce wallee (Version 1.3.3)
PHP-Version 7.2.26-1+ubuntu18.04.1+deb.sury.org+1###

WooCommerce: 3.9.2
#

Fehler-Details
==============
Ein Fehler vom Typ E_ERROR wurde in der Zeile 639 der Datei /home/s11/html/wp-content/plugins/woo-wallee/woocommerce-wallee.php verursacht. Fehlermeldung: Uncaught Error: Call to undefined function is_checkout() in /home/s11/html/wp-content/plugins/woo-wallee/woocommerce-wallee.php:639
Stack trace:
#0 /home/s11/html/wp-includes/class-wp-hook.php(288): WooCommerce_Wallee->add_cache_no_store(Array)
#1 /home/s11/html/wp-includes/plugin.php(206): WP_Hook->apply_filters(Array, Array)
#2 /home/s11/html/wp-includes/functions.php(1429): apply_filters(‘nocache_headers’, Array)
#3 /home/s11/html/wp-includes/functions.php(1451): wp_get_nocache_headers()
#4 /home/s11/html/wp-admin/admin.php(36): nocache_headers()
#5 /home/s11/html/wp-admin/update.php(14): require_once(‘/home/s11/html/…’)
#6 {main}
thrown####