After an enchanted or renamed block is placed on the ground and picked back up it is not enchanted or renamed anymore. I had a renamed torch that I accidentally placed on the wall and when I picked it back up it wasn't renamed and I had to go use another 5 levels to rename it again which also happened to break my anvil!
Related issues
duplicates
Comments
Duplicate of MC-209.
For all intents and purposes this "works as intended". Blocks can't save the meta-data required to remember names and enchantments. The feature wasn't really intended to be used for those items.