unable to repair pickaxe in worktable

Put the summary of the bug you're having here

What I expected to happen was...:
I should have been able to pick up a Describe what you thought should happen here

When I put two used pickaxes into the boxes on the 3x3 or 2x2 the game does not allow an upgraded pickaxe to be taken.  i.e. two used (red) pickaxes are placed in the workbench and a yellow or green pickaxe should be available.  this feature doesn't work.  Is this an action not allowed (as it was in earlier games) or is this a bug?   

What actually happened was...:
no upgraded item available. 

Steps to Reproduce:
1. Put two used pickaxes in the worktable box 

2. no repaired/upgraded item is available .