On-board map calibrator fault

Is this happen to you all the time? Because when I do these steps

1. open Onn-board calibrator
2. "Take" image
3. press "Add" to add first calibration point
4. pick on map
5. tap on "map" and set geo coordinates
6. press "Add" to add second calibration point
7. pick on map
8. tap on "map" and set geo coordinates
9. press "Add" to add third calibration point
10. pick on map
11. tap on "map" and set geo coordinates
12. press "Add" to add fourth calibration point
13. pick on map
14. tap on "map" and set geo coordinates
15. tap "Compute" to check if it's possible to create image
16. tap "No" to return back
    
17. tap "Delete" on all four calibration points with comfirmation "Delete"

After all these steps, "Add" button is still enabled even so I can start adding new calibration points.

May you write me what you do in a different way so I can simulate your problem? Thanks

I didn't shoot img with camera, I've picked it from phone memory (I don't expect this to cause the problem, just want to be accurate)

2. pick image from phone memory

.....

16. tap "Yes" to save

17. Open on-board menu again

18. pick image from phone memory

19. tap clear

20. bug

ah got it, so "Clear" button cause troubles. Perfect, thank you.