UIGestureRecognizer.State is 'possible' and not 'recognized' every other click on an MKMapView

I am trying to understand a reproducible bug with my gesture recognisers. I have 2 recognisers on an MKMapView, one UITapGestureRecognizer and one UILongPressGestureRecogniser. Both of them work as expected the first time, however, if I use the long press (which adds an annotation to the map) the next tap gesture will return in the 'possible' state but never hit the 'recognized' state.

▿ Optional<Array<UIGestureRecognizer>>
  ▿ some : 2 elements
    - 0 : <UITapGestureRecognizer: 0x7fda7543ebc0; state = Possible; view = <MKMapView 0x7fda78026e00>>
    - 1 : <UILongPressGestureRecognizer: 0x7fda7543e8c0; state = Possible; view = <MKMapView 0x7fda78026e00>; numberOfTapsRequired = 0; minimumPressDuration = 0.2>

After I tap once, and nothing happens, a second tap will then perform the associated function i.e. make it to the recognized state.

I am intercepting all the clicks on the window and the tap definitely takes place each time but the first one after a long press never seems to become accepted. Is there something I'm missing here? The gestures are added as below:

let mapTap = UITapGestureRecognizer(target: self, action: #selector(mapTapped(_:)))
        mapView.addGestureRecognizer(mapTap)

let pressGesture = UILongPressGestureRecognizer(target: self, action: #selector(mapLongPress(_:)))
            pressGesture.minimumPressDuration = 0.2
            pressGesture.numberOfTouchesRequired = 1
            mapView.addGestureRecognizer(pressGesture)

Could this be to do with the other gestures which are added by default on an MKMapView?

from UIGestureRecognizer.State is 'possible' and not 'recognized' every other click on an MKMapView