I was trying to make villager shops. For their workstation, I placed smithing tables on the floor. Then I would wait until the villager sets their profession. Since it was nighttime when I was making these shops, I used /time add 1000 until it became daytime, then I summoned in the villagers. However, they would not set their profession even when they are standing on top of a workstation.

I discovered that it was not because of a maximum limit of villagers with a certain profession in a village, because when I placed down other workstations, they still did not set their profession. I tried killing the villagers then spawning in more villagers, however, they still did not set their profession. I also tried placing a bed and letting a villager sleep in it, which did not help either.