Call to undefined function update_term_meta()

Is possible conflict with the plugin.
You can try to turn off one by one, plugin meta.

Please update your WordPress to the latest version.

I tried to assume it was another plugin. But removed them all and still got the error. Sorry, but I won’t upgrade. I’m committed to this version. Too bad. I really liked to use your plugin. But the error is Fatal error: Call to undefined function update_term_meta() in *************** \plugins\asgaros-forum\admin\admin.php on line 155
Call Stack
# Time Memory Function Location
1 0.0010 275888 {main}( ) ..\admin-ajax.php:0
2 0.5648 42887208 do_action( ) ..\admin-ajax.php:89
3 0.5648 42888680 call_user_func_array:{************\wp-includes\plugin.php:503} ( ) ..\plugin.php:503
4 0.5648 42889080 wp_ajax_add_tag( ) ..\plugin.php:503
5 0.5648 42890776 wp_insert_term( ) ..\ajax-actions.php:796
6 0.5804 42927696 do_action( ) ..\taxonomy.php:3044
7 0.5804 42929296 call_user_func_array:{************\wp-includes\plugin.php:503} ( ) ..\plugin.php:503
8 0.5804 42929368 asgarosforum_admin->save_category_form_fields( ) ..\plugin.php:503

Okay, you plugin states 4.3 or greater, but you use get_term_meta which isn’t available until 4.4 ??

Yes, I made some changes recently and forgot to adjust the requirement-value in the readme file. I will change it with the next release.