I think you're using custom cell. So problem may be in this line. MKMapView *MapView = (MKMapView*)[header viewWithTag:2];
Instead try this.
MKMapView *MapView = (MKMapView*)[header.contentView viewWithTag:2];
And they go with this .
[header.contentView sendSubviewToBack:MapView];
Note: If all content's subview have bounds less than MKMapView
means, MKMapView
always will be in screen.