Route matrix failed error when doReverseGeocode = false, but successful when true

When using routematrix, and doReverseGeocode = false, we are getting 602 error.  When it is set to true, we get status code = 0.  Any idea what is causing the 602?

https://www.mapquestapi.com/directions/v2/routematrix?key=<key>

{
    "locations": [
        "42.422083, -123.335506",
        "39.48053, -119.79178"

    ],
    "options": {
        "doReverseGeocode": false,
    }
}

Results:

602:

Route matrix failed - unknown error in route computation