I wonder if anyone had/has this issue.
While flying in Arizona, in the bumps (sometimes I feel like a bug being shaken in a can) I had forgotten to reverse my route in the flight plan. While trying to hit the 'Reverse Route' button right next to the 'Clear' button, you guessed it, I hit the Clear button. The dialogue box didn't give an option to cancel. You can see in the picture you only have two options to clear active or clear both active and alternate. This was unnerving to say the least. There should have been a cancel button I thought.
All was not lost because with no other way to get past the dialogue box other than to Clear. Fortuitously after Clearing I was presented with a 'Restore' option.