Put the summary of the bug you're having here
What I expected to happen was...:
A regular villager that was unemployed.
What actually happened was...:
The villager became a librarian once cured and had no lecturn nearby that would cause this
Steps to Reproduce:
I just cured a villager and it automatically got a profession but cant refresh trades because he is locked to a lecturn that doesn't exist or something. (I tried placing other profession blocks and even a lecturn but it did not fix the issue
Have you traded with the villager before?