the sketch is gone

[adrenalina100]

Hello, everyone.
I was correcting a sketch and at some point I exploded the logical tree. the sketch has become faded green color.
after correcting some quotas on the sketch I saved in the same starting file, but when I reopened this file the sketch there was no longer.
I am using catia v5-6r2018; could it be a program bug?

 

[gianni55]

I doubt that the sketch has disappeared, if it has become faded it is because by exploding it you clicked on a "branch" of the tree, explode it again and click on a branch

 

[adrenalina100]

Thanks, it worked.