diff --git a/comfyrecipes/parsing.py b/comfyrecipes/parsing.py
index 65ae589..7f73140 100644
--- a/comfyrecipes/parsing.py
+++ b/comfyrecipes/parsing.py
@@ -564,7 +564,7 @@ class PriceDB(Element):
         price: float,
         amount: float,
         unit: Unit,
-        currency: Optional[str],
+        currency: str,
     ) -> None:
         super().__init__(ctx)
         self.price = price
@@ -591,4 +591,6 @@ class PriceDB(Element):
         currency = ctx.settings.default_currency
         if "currency" in dct:
             currency = dct["currency"]
+        if currency is None:
+            raise RuntimeError("currency not specified and default_currency is also not set")
         return cls(ctx=ctx, price=price, amount=amount, unit=unit, currency=currency)