It happened to me when I rescued a mistreated Doberman. This large girl dog was skinny, neglected, and oh so hungry for love and care. And boy could that dog jump.
I bought a new five foot high wire enclosure, the portable kind, and placed her in the living room so I could watch her - she needed confinement and did not take to a crate of any type. Well, the first thing she does is jump over and out, not once but several times. This is never going to work.
So, I solved the problem by placing a long board across the top of the enclosure and on the board put several metal dog bowls. The next time she tried to jump out, the board fell, the pans clanged, and the noise startled her. That did the trick, she no longer tries to escape as long as the board is on top. The board works fine because I can remove it easily - this is one possible solution. I don't use shock collars in training and try to be as creative as I can in solving problem dog behavior.