How to update only one input in Laravel form?

working with laravel and mysql. I have user update form with name,email,password and conform password with following controller validation,

$this->validate($request, [
            'name' =>'required',
            'email' => 'required|email',
            'password' => 'sometimes|min:6|confirmed'
  ]);

in my form normaly users do not update this all input fields. as an example some user need update only email. but with above validation when we update only name or email validation display message The password must be at least 6 characters. then how can do only name or email update without password update?

via Chebli Mohamed