I can't switch into hardmode but I can break altars and no hollow spawned

I killed WoF (wall of flesh) 5 times already and it won't let me enter hardmode.

I get the pwnhammer, I can destroy altars, but I don't get new ores spawning from destroying the altars and the hollow didn't spawn in my world after beating WoF. Is this a bug or something?

Solution 1:

From the Terraria Wiki:

The first three Demon Altars destroyed will trigger the creation of three new Ores, in the following order:

The first destroyed Demon Altar or Crimson Altar will trigger the creation of Cobalt Ore or Palladium Ore. The second destroyed Demon Altar or Crimson Altar will trigger the creation of Mythril Ore or Orichalcum Ore. The third destroyed Demon Altar or Crimson Altar will trigger the creation of Adamantite Ore or Titanium Ore.

Did you destroy at least 3? It also says that Hallow and Crimson/Corruption should spawn upon its death, not the altars. If that's not the case, i would assume it is a bug yes.

Else see this post from someone with a similar issue on reddit.