Hello alekz!
This might be a stupid question but do your characters actually have any Identify spells memorised or Identify scrolls in their inventories?
If that isn't the problem, then it might be a bug...have you installed the patch?
You could always take HaerDelis in your party, he has a very high lore, which means he'll be able to identify lots of things without using the Identify spell.
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Melusine, Archbabe of the OHF and the LH
Your voice is ambrosia