Said they buried service line but never did

So I been trying to get a hold of xfinity about a service line they said they buried but they did not bury. The utility service come out and marked yard many many days ago but no one has showed to bury it. The line runs through my neighbors yard and he is threatening to cut it if someone does not show and I cant get through to a service rep. They sure have no problem showing to install a service when ordered but dont take calls after that and im getting highly irritated.