After the player purchases the same item several times, the wandering trader locks the trade, but unlike villagers, never unlocks the trade. The wandering trader can appear again around the player with new trades after a while.

How do wandering villagers restock?

After the time expires, the wandering trader despawns, even if the wandering trader is named with a name tag or put in a vehicle such as a minecart or boat. A wandering trader despawns sooner if all trades have been locked. The trader may later respawn with new trades.

How often do wandering traders restock?

As described in the title. Wandering traders still use the villagers text "Villagers restock up to two times a day" even though their trades can never restock.