Plugin Issue

We are getting Warning message with the plugin,listed below

Warning: Missing argument 2 for Jetpack_Sync_Module_Users::wp_login_handler(), called in /home3/path/class-wp-hook.php on line 286 and defined in /home3/path/class.jetpack-sync-module-users.php on line 175

Warning: Cannot modify header information - headers already sent by (output started at /home3/path/class.jetpack-sync-module-users.php:175) in /home3/path/pluggable.php on line 1251

Warning: Cannot modify header information - headers already sent by (output started at /home3/path/class.jetpack-sync-module-users.php:175) in /home3/path/pluggable.php on line 1254

Which we fiexd using the following code:

if($user = null){
			$user = wp_get_current_user();
		}

We request you to make the necessary changes at your end to fix this error or let us know if there is any other method which we can opt as I am not comfortable in making the changes in the plugin to fix this.
Looking for a positive and prompt response from your side.

Thanks.