Realm accessed from incorrect thread

[Jay (Jason Wooten)]

@Igor_Stasiv

 DispatchQueue.global(qos: .background).async {
   let realmBackground = try! Realm()
   for oldPoi in realmBackground.objects(SmallPOI.self).filter("name_implan == %@", implan) {
      if !newPois.contains(oldPoi.smallPOIUID ?? "") {
         try! realmBackground.write { realmBackground.delete(oldPoi) }
      }
    }
  }

What happens if you do this as a test; comment out all of the above and replace it with this

let realmBackground = try! Realm()
let implanResults = realmBackground.objects(SmallPOI.self).filter("name_implan == %@", implan)
for implan in implanResults {
   print(implan)
}

And see if it crashes and if so, on what line.