Can’t create a badge

after install and activated myCred – Learndash, I can’t create a badge. If only install and activated myCred, I can create a badge.

And have error

Thông tin lỗi
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Có lỗi E_ERROR tại dòng 917 trong file: /var/www/html/wp-content/plugins/mycred-learndash/inc/class-mycred-learndash-leaderboard.php. Thông báo lỗi: Uncaught TypeError: Cannot access offset of type string on string in /var/www/html/wp-content/plugins/mycred-learndash/inc/class-mycred-learndash-leaderboard.php:917
Stack trace:
#0 /var/www/html/wp-content/plugins/mycred-learndash/inc/class-mycred-learndash-leaderboard.php(859): MyCred_Learndash_Leaderboard->mycred_leaderboard_generate_shortcode()
#1 /var/www/html/wp-includes/class-wp-hook.php(324): MyCred_Learndash_Leaderboard->mycred_learndash_leaderboard_save()
#2 /var/www/html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters()
#3 /var/www/html/wp-includes/plugin.php(517): WP_Hook->do_action()
#4 /var/www/html/wp-includes/post.php(4828): do_action()
#5 /var/www/html/wp-admin/includes/post.php(766): wp_insert_post()
#6 /var/www/html/wp-admin/post-new.php(66): get_default_post_to_edit()
#7 {main}