In my world that I upgraded from 1.13 to 1.14 my villagers are not refreshing their trades. I have seen the It will Refresh twice a day thing but I have waited ~10 days and It hasn't refreshed. It is a realm if It changes anything. Thanks!
Have you given them appropriate workstations and beds?
They seem to have to use a workstation to refresh the trades, I don't know if they need beds or not.
Note that they seem to be able to pick a workstation from quite a long way off but have to get right up to it to refresh the trades so fencing them in might not be a good idea if they can pick a workstation outside their fence.