AT commands always return NIL

[Cleversou1983]

Hi there, when I try to use an AT commando (like At.voltage), the Framework prints on the console the info, but looks like it doesn't store it on the DATA variable...

Set OBD protocol to Optional(OBD2.ScanProtocol.CAN29bit250KB)
Write to OBD Optional("AT RV\r")
Wrote 6 bytes
Read 10 bytes
Read complete
12.4V

Optional(OBD2.Response(timestamp: 2018-01-01 23:22:58 +0000, mode: OBD2.Mode.none, pid: 0, data: nil, rawData: [49, 50, 46, 52, 86, 13, 10, 0, 10, 62], strigDescriptor: nil))

Thanks...