fatal error

i am facing issue in activating easync plugin.Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($function) must be a valid callback, function "sync_currency_list" not found or invalid function name in C:\xampp\htdocs\carbook\wordpress\wp-includes\class-wp-hook.php:303 Stack trace: #0 C:\xampp\htdocs\carbook\wordpress\wp-includes\class-wp-hook.php(327): WP_Hook->apply_filters(NULL, Array) #1 C:\xampp\htdocs\carbook\wordpress\wp-includes\plugin.php(470): WP_Hook->do_action(Array) #2 C:\xampp\htdocs\carbook\wordpress\wp-admin\plugins.php(193): do_action('activate_easync...') #3 {main} thrown in C:\xampp\htdocs\carbook\wordpress\wp-includes\class-wp-hook.php on line 303
this is the error. please can you help me resolve

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