villagers have trouble changing jobs.

If you've already leveled up a villager, he will be "locked in" to the profession and trades he currently has. This is intended behavior. 

Yes, the problem is that i never traded with him.

Is the fisherman linked to a barrel?

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However, this issue has been temporarily closed as Awaiting Response

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Cleaning up old tickets: This ticket had been set to 'Awaiting Response', but has not received a response from the reporter (~3 months+) so is being closed as Incomplete. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines which includes steps to reproduce the problem.

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