Question about building construction.

Good evening. Perhaps there is a limit on building a specific structure on the map; this sometimes happens.
Are you playing on a standard map, in the HotA campaign, or did you download it from the forum?

No, it's a standard map against bots. It's called "In Search of Peace." A limit on upgrading buildings with bears and the Magistrate's buildings? It seems unlikely that a map without restrictions would limit the construction of basic buildings.
A similar situation occurred on a standard map before. Could it be some kind of bug?