diff --git a/src/akkudoktoreos/server/eos.py b/src/akkudoktoreos/server/eos.py
index 3d8f0124..8fd19e13 100755
--- a/src/akkudoktoreos/server/eos.py
+++ b/src/akkudoktoreos/server/eos.py
@@ -993,7 +993,11 @@ def fastapi_prediction_import_provider(
     if not provider.enabled() and not force_enable:
         raise HTTPException(status_code=404, detail=f"Provider '{provider_id}' not enabled.")
     try:
-        provider.import_from_json(json_str=data.model_dump_json() if hasattr(data, "model_dump_json") else json.dumps(data))
+        if isinstance(data, (PydanticDateTimeDataFrame, PydanticDateTimeData)):
+            json_str = data.model_dump_json()
+        else:
+            json_str = json.dumps(data)
+        provider.import_from_json(json_str=json_str)
         provider.update_datetime = to_datetime(in_timezone=get_config().general.timezone)
     except Exception as e:
         raise HTTPException(
@@ -1662,4 +1666,4 @@ def main() -> None:
 
 
 if __name__ == "__main__":
-    main()
+    main()
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