/rangemap API required deviceTime queryString

[hkmemory]

When I submit a GET method request to Rangemap API, it show the following error message.
{
"error": {
"code": 500,
"description": "(SmartPhoneUtil-A-101) Mandatory parameter(s) missed or blank: Cannot calculate remaining range circle, deviceTime is missing!"
}
}

After I added the (deviceTime=1) queryString it show other error message
{
"error": {
"code": 500,
"description": "(SmartPhoneUtil-A-2012) Ressource not found. Cannot calculate remaining range circle!"
}
}

What should I input at deviceTime queryString?
Thanks.