diff --git a/aioqsw/localapi.py b/aioqsw/localapi.py
index a5aed33..f51360a 100644
--- a/aioqsw/localapi.py
+++ b/aioqsw/localapi.py
@@ -301,7 +301,10 @@ async def check_firmware(self) -> FirmwareCheck:
 
         fw_check = await self.get_firmware_update_check()
         await self.set_api_raw_data(RAW_FIRMWARE_CHECK, fw_check)
-        self.firmware_check = FirmwareCheck(fw_check)
+        if self.firmware_check is None:
+            self.firmware_check = FirmwareCheck(fw_check)
+        else:
+            self.firmware_check.update_data(fw_check)
 
         return self.firmware_check