The default scenery for this airport ( which from your log is what GSX is using ), doesn't have any parkings so, GSX would normally deny any service there, with a message.
But I see you have a GSX custom profile for it, could be it was made for P3D4 ? I checked the P3D V4 version of the airport, and it *does* have 5 parking spots, while the P3D V5 version has none ( just a fuel parking ) but, since the .BGL is named the same, GSX is still using the custom profile you made for P3D V4, but now the parking spots do not exists anymore.
If you remove the custom profile ( the .INI in %APPDATA%\virtuali\GSX ), and restart Couatl or start the sim, the error will away, and GSX will tell you can't use that airport, because it has no parking spots, as it normally should.