diff --git a/src/caosadvancedtools/table_json_conversion/convert.py b/src/caosadvancedtools/table_json_conversion/convert.py
index beb7841a491424454b3d4a9f21ce8aae948d3a0d..ab25981234a3d045b60e474e8900fbe75c19d091 100644
--- a/src/caosadvancedtools/table_json_conversion/convert.py
+++ b/src/caosadvancedtools/table_json_conversion/convert.py
@@ -329,7 +329,12 @@ class XLSXConverter:
                                      for e in exceptions])
                 raise jsonschema.ValidationError(mess)
         if validate:
-            jsonschema.validate(self._result, self._schema)
+            for dtype, items in self._result.items():
+                sub_schema = self._schema["properties"].get(dtype)
+                if dtype is None:
+                    raise KeyError(f"Type not found in schema's properties: {dtype}")
+                for item in items:
+                    jsonschema.validate(item, sub_schema)
         if self._errors:
             raise RuntimeError("There were error while handling the XLSX file.")
         return self._result