It could a neighbour's device. Unless you saying that 13:077615 is definitely yours.
According to me 31 is a wireless stat and might not even be called Honeywell.
And in any case it can't be the HC60NG because that device cannot respond to any requests. It's a listen only radio device, which is why I think it was quickly replaced by the BDR91 that can perform 2 way radio communications.