diff --git a/custom_components/localthings/config_flow.py b/custom_components/localthings/config_flow.py
index fa986cd..8b0e097 100644
--- a/custom_components/localthings/config_flow.py
+++ b/custom_components/localthings/config_flow.py
@@ -91,7 +91,7 @@ def _fetch_samsung_uuid() -> str:
         raise RuntimeError(f"No certificate received from {_SAMSUNG_CLOUD_HOST}")
     cert = _x509.load_der_x509_certificate(der)
     for attr in cert.subject:
-        if attr.oid == _x509.oid.NameOID.ORGANIZATIONAL_UNIT_NAME:
+        if attr.oid == _x509.oid.NameOID.ORGANIZATIONAL_UNIT_NAME and isinstance(attr.value, str):
             m = re.search(r"uuid:([0-9a-f-]+)", attr.value, re.IGNORECASE)
             if m:
                 return m.group(1)
diff --git a/custom_components/localthings/sensor.py b/custom_components/localthings/sensor.py
index 4d98c33..eccbb3e 100644
--- a/custom_components/localthings/sensor.py
+++ b/custom_components/localthings/sensor.py
@@ -5,7 +5,7 @@ from __future__ import annotations
 from datetime import timedelta
 from typing import cast
 
-from homeassistant.components.sensor import SensorDeviceClass, SensorEntity
+from homeassistant.components.sensor import SensorDeviceClass, SensorEntity, SensorStateClass
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import EntityCategory
 from homeassistant.core import HomeAssistant
@@ -47,7 +47,7 @@ class LocalThingsSensor(LocalThingsEntity, SensorEntity):
         self._attr_device_class = (
             SensorDeviceClass(desc.device_class) if desc.device_class else None
         )
-        self._attr_state_class = desc.state_class
+        self._attr_state_class = SensorStateClass(desc.state_class) if desc.state_class else None
         if desc.options:
             self._attr_options = list(desc.options)
         self._hysteresis_value = None