Huawei HG8546M TR-069 Integration

I am trying to change the password on huawei HG8546M through TR-069 with parameter:
InternetGatewayDevice.LANDevice.1.WLANConfiguration.1.PreSharedKey.1PreSharedKey
But when downloading the parameter list it shows:

Parameter Object
InternetGatewayDevice.LANDevice.1.WLANConfiguration.1.KeyPassphrase FALSE

Is this the issue, Help