diff --git a/device/device_olt.go b/device/device_olt.go
index 5f34a03..b3dc2c3 100644
--- a/device/device_olt.go
+++ b/device/device_olt.go
@@ -48,8 +48,8 @@
 	Name               string
 	InternalState      DeviceState
 	OperState          string
-	NniIntfs		   []nniIntf
-	PonIntfs		   []ponIntf
+	NniIntfs           []nniIntf
+	PonIntfs           []ponIntf
 	HeartbeatSignature uint32
 	mu                 *sync.Mutex
 }
@@ -186,4 +186,4 @@
 func (olt *Olt) UpdatePonPortState(portID uint32, alarmState AlarmState, operState string) {
 	olt.PonIntfs[portID].AlarmState = alarmState
 	olt.PonIntfs[portID].OperState = operState
-}
\ No newline at end of file
+}