UISearchcontroller does not work after unwind segue

I have a UISearchController with a tableview which displays the searched PFusers from Parse. When the user tab on a row, the cell will segue to another view controller displaying info about the PFUser. The segued view controller has a button to unwind segue back to the tableview. The problem happens when I segue back to the tableviewcontroller; the tableviewcontroller is no longer like it was before I segue to another view controller (the searched PFUsers are gone, the table is empty) and when I search again, no results are fetched but I can see it is using data because of the spinner on the battery status bar. Any idea why this is happening? thanks!