Unable to Set Terms for Custom Post Types

I have created two types of taxonomies for two different custom post types using Custom Post Type UI. However, for the second taxonomy created, although it appears on the post editing screen, I am unable to add any terms. When I enter a term and press enter, nothing gets added, and I receive an error message stating, “No route was found matching the URL and request method.”

The first taxonomy created functions without any issues.

Both WordPress and the plugins are up to date.

The settings for the taxonomy are as follows:
public: true
publicly_queryable: true
hierarchical: true
show_ui: true
show_in_menu: true
show_in_nav_menus: true
query_var: true
query_var_slug: “”
rewrite: true
rewrite_slug: “”
rewrite_withfront: true
rewrite_hierarchical: false
show_admin_column: false
show_in_rest: true
show_tagcloud: false
sort: false
show_in_quick_edit: “”
rest_base: “”
rest_controller_class: “”
rest_namespace: “”
meta_box_cb: “”
default_term: “”

If you have any insights into the possible cause of this issue, I would greatly appreciate your guidance. I apologize for my limited English skills.

I am sorry to bother you when you are busy, but I kindly ask for your assistance.