Fix OVO Energy Sensors
diff --git a/homeassistant/components/ovo_energy/__init__.py b/homeassistant/components/ovo_energy/__init__.py
index 3aff51fa044ee3..e98e81ba1c2f02 100644
--- a/homeassistant/components/ovo_energy/__init__.py
+++ b/homeassistant/components/ovo_energy/__init__.py
@@ -40,7 +40,14 @@ async def async_update_data() -> OVODailyUsage:
         """Fetch data from OVO Energy."""
         now = datetime.utcnow()
         async with async_timeout.timeout(10):
-            return await client.get_daily_usage(now.strftime("%Y-%m"))
+            try:
+                await client.authenticate(
+                    entry.data[CONF_USERNAME], entry.data[CONF_PASSWORD]
+                )
+                return await client.get_daily_usage(now.strftime("%Y-%m"))
+            except aiohttp.ClientError as exception:
+                _LOGGER.warning(exception)
+                return None
 
     coordinator = DataUpdateCoordinator(
         hass,
diff --git a/homeassistant/components/ovo_energy/sensor.py b/homeassistant/components/ovo_energy/sensor.py
index 4b9e2e7080682d..a0781836d6c859 100644
--- a/homeassistant/components/ovo_energy/sensor.py
+++ b/homeassistant/components/ovo_energy/sensor.py
@@ -29,15 +29,29 @@ async def async_setup_entry(
 
     entities = []
 
-    if coordinator.data.electricity:
-        currency = coordinator.data.electricity[
-            len(coordinator.data.electricity) - 1
-        ].cost.currency_unit
-        entities.append(OVOEnergyLastElectricityReading(coordinator, client))
-        entities.append(OVOEnergyLastElectricityCost(coordinator, client, currency))
-    if coordinator.data.gas:
-        entities.append(OVOEnergyLastGasReading(coordinator, client))
-        entities.append(OVOEnergyLastGasCost(coordinator, client, currency))
+    if coordinator.data:
+        if coordinator.data.electricity:
+            entities.append(OVOEnergyLastElectricityReading(coordinator, client))
+            entities.append(
+                OVOEnergyLastElectricityCost(
+                    coordinator,
+                    client,
+                    coordinator.data.electricity[
+                        len(coordinator.data.electricity) - 1
+                    ].cost.currency_unit,
+                )
+            )
+        if coordinator.data.gas:
+            entities.append(OVOEnergyLastGasReading(coordinator, client))
+            entities.append(
+                OVOEnergyLastGasCost(
+                    coordinator,
+                    client,
+                    coordinator.data.gas[
+                        len(coordinator.data.gas) - 1
+                    ].cost.currency_unit,
+                )
+            )
 
     async_add_entities(
         entities, True,

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## Proposed change
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- Fixes no electricity currency value
- Fixes update unknown issue #38824

Tested over a few hours. All seems well and updates/does not set an unknown state

## Type of change
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## Additional information
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- This PR fixes or closes issue: fixes #38824
- This PR is related to issue: #38824
- Link to documentation pull request: N/A 

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