xampp pluguin not active

fatal error: uncaught typeerror: call_user_func_array(): argument #1 ($callback) must be a valid callback, function "sync_currency_list" not found or invalid function name in c:\xampp\htdocs\oxcarrental\wp-includes\class-wp-hook.php:307 stack trace: #0 c:\xampp\htdocs\oxcarrental\wp-includes\class-wp-hook.php(331): wp_hook->apply_filters(null, array) #1 c:\xampp\htdocs\oxcarrental\wp-includes\plugin.php(474): wp_hook->do_action(array) #2 c:\xampp\htdocs\oxcarrental\wp-admin\plugins.php(194): do_action('activate_easync...') #3 {main} thrown in c:\xampp\htdocs\oxcarrental\wp-includes\class-wp-hook.php on line 307

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