diff --git a/yolink/device.py b/yolink/device.py
index a2fbcda..b6e3cd6 100644
--- a/yolink/device.py
+++ b/yolink/device.py
@@ -4,7 +4,11 @@
 from typing import Optional
 
 from tenacity import RetryError
-from pydantic import BaseModel, Field, validator
+
+try:
+    from pydantic.v1 import BaseModel, Field, validator
+except ImportError:
+    from pydantic import BaseModel, Field, validator
 
 from .client import YoLinkClient
 from .exception import YoLinkClientError
diff --git a/yolink/model.py b/yolink/model.py
index 8357d9f..e7af8f7 100644
--- a/yolink/model.py
+++ b/yolink/model.py
@@ -1,6 +1,10 @@
 """YoLink Basic Model."""
 from typing import Any, Dict, Optional
-from pydantic import BaseModel
+
+try:
+    from pydantic.v1 import BaseModel
+except ImportError:
+    from pydantic import BaseModel
 
 from .exception import (
     YoLinkAuthFailError,
@@ -12,11 +16,11 @@
 class BRDP(BaseModel):
     """BRDP of YoLink API."""
 
-    code: Optional[str]
-    desc: Optional[str]
-    method: Optional[str]
-    data: Dict[str, Any]
-    event: Optional[str]
+    code: Optional[str] = None
+    desc: Optional[str] = None
+    method: Optional[str] = None
+    data: Dict[str, Any] = None
+    event: Optional[str] = None
 
     def check_response(self):
         """Check API Response."""
diff --git a/yolink/mqtt_client.py b/yolink/mqtt_client.py
index 2a34fb7..f31e43f 100644
--- a/yolink/mqtt_client.py
+++ b/yolink/mqtt_client.py
@@ -3,7 +3,12 @@
 import logging
 from typing import Any
 import aiomqtt
-from pydantic import ValidationError
+
+try:
+    from pydantic.v1 import ValidationError
+except ImportError:
+    from pydantic import ValidationError
+
 from .auth_mgr import YoLinkAuthMgr
 from .const import (
     YOLINK_API_MQTT_BROKER,
diff --git a/yolink/thermostat_request_builder.py b/yolink/thermostat_request_builder.py
index e9769f2..aa2fa1e 100644
--- a/yolink/thermostat_request_builder.py
+++ b/yolink/thermostat_request_builder.py
@@ -2,7 +2,11 @@
 from __future__ import annotations
 
 from typing import Optional
-from pydantic import BaseModel
+
+try:
+    from pydantic.v1 import BaseModel
+except ImportError:
+    from pydantic import BaseModel
 
 from .client_request import ClientRequest
 
@@ -10,11 +14,11 @@
 class ThermostatState(BaseModel):
     """Thermostat State."""
 
-    lowTemp: Optional[float]
-    highTemp: Optional[float]
-    mode: Optional[str]
-    fan: Optional[str]
-    sche: Optional[str]
+    lowTemp: Optional[float] = None
+    highTemp: Optional[float] = None
+    mode: Optional[str] = None
+    fan: Optional[str] = None
+    sche: Optional[str] = None
 
 
 class ThermostatRequestBuilder:  # pylint: disable=too-few-public-methods