1 files changed, 8 insertions, 2 deletions
diff --git a/openbb_platform/core/openbb_core/provider/standard_models/cash_flow.py b/openbb_platform/core/openbb_core/provider/standard_models/cash_flow.py
index a2495a26da1..c3c12e777bb 100644
--- a/openbb_platform/core/openbb_core/provider/standard_models/cash_flow.py
+++ b/openbb_platform/core/openbb_core/provider/standard_models/cash_flow.py
@@ -24,10 +24,16 @@ class CashFlowStatementQueryParams(QueryParams):
 
     @field_validator("symbol", mode="before", check_fields=False)
     @classmethod
-    def upper_symbol(cls, v: str):
-        """Convert symbol to uppercase."""
+    def to_upper(cls, v: str):
+        """Convert field to uppercase."""
         return v.upper()
 
+    @field_validator("period", mode="before", check_fields=False)
+    @classmethod
+    def to_lower(cls, v: Optional[str]) -> Optional[str]:
+        """Convert field to lowercase."""
+        return v.lower() if v else v
+
 
 class CashFlowStatementData(Data):
     """Cash Flow Statement Data."""