When you have a fully maxed out piece of armor to where you cant repair/add any other enchantments onto it. When you disenchant that item with a grindstone know that there are zero enchants on it. And you still cant do anything with it, E.g. rename or add enchants, and it displays the message "Too Expensive!" in the anvil.
Thank you for your report!
We're actually already tracking this issue at MCPE-45130, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
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