With the new Trading Post Rewards for March 2023, players found to their disappointment that the item they have frozen is no longer showing up. Blizzard has now acknowledged this issue and promises a hotfix soon!
We’re aware of the issues people are experiencing and are working on them. Of note, if you froze an item from last month, don’t refreeze anything else. We believe this is a display error that we are working to correct. Players will likely need to log out and back in once the fix has been added to the game to see the item again.