Adding parking to existing airport creates duplicate ICAO in GPS

I am having an issue. I want to add a parking spot at several airports and add a helipad over that parking spot. In order to add either I have to first add airport. I do this and use the same ICAO code as the existing airport and the same name in the properties. I can then add a parking spot and then place a helipad over that parking spot. save and build the project and load it in the sim and all works as I want it to except when I go to my GPS to create a flight somewhere and I put the ICAO in for the airport that I edited it shows “duplicate found” and I have to select one of the two and then it works. Which is OK, it works, but I realize I must be doing something wrong because there shouldn’t be a duplicate ICAO.
Please help.

It sounds like you’re trying to add airport features (add an airport), without deleting the old airport. If you’re wanting to add parking etc, you’re going to have to rebuild the whole airport.

The best path is to use Airport Design Editor to create an airport project from an existing airport. It will automatically set the variables to delete the old airport. Then you can modify the existing airport project as you like.