Stuff has gone.

I had 29 level. I wanted to repair my diamond pickaxe (Efficiency 4, unbraking 3, silk touch) + the full durability stock diamond pickaxe through the anvil, it cost 5 levels. When I pressed the fixed pickaxe in the anvil, somehow he gone and my level (5 levels) gone too. I tried to reload the map, restart the computer, everything I tried, but still nothing. It is a bug or new update or something ?