Employee based interview I485


My question is regarding to employment based interview for status adjustment. My interview was scheduled on August 2018. The interview went good. IO said everything is good and i am approving your application but there is no visa available at the moment. Your status is kind of pre-approved. I don’t have any question, just keep watching the dates. When it becomes current you will be issued green Card. Now since October, dates for us are current but it has been 15 days and no update on my case. I am not sure why it is taking so much time. Even though my application is approved according to IO.