When trading with villagers it is very common to have some tools from inventory disappear after the trade.
I don't know if it happens to other items, but when I get an enchanted axe, sword or pic missing I notice instantly. It has happened multiple and is very easy to reproduce.
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-18617.
It has been linked to this report. If you have additional information, please add it to that report.
If you have not, please search before reporting, as it's likely that one exists already.
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