Dears,
A cured zombievillager is not able losing his profession. even when a bed and professionblock is placed during cure, its not responding.
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Thank you for your report!
However, this issue is a Duplicate of MCPE-48712.
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This occurs on all versions of Bedrock current version (1.12.1). Cured a zombie villager, who became Fisherman. UI indicated that this villager had had a trade performed (some progress on trade XP bar) which is impossible as this zombie villager was a natural spawn, not a villager converted by a zombie attack. No other jobsite blocks except for Lectern for 300 block radius, never changed profession. Cured villager acts as if an initial trade was performed, locking the profession