How is your router connected to the ONT? Via coax or via cat5?
My guess is that you have a coax connection from the ONT to your router and the DirecTv installer took over the coax wiring in the house for the DirectTv install.
You have a couple of choices:
1) Run a new piece of coax from the ONT to the router. Do not connect it to any splitters used by DirecTv.
2) Run a cat5 cable from the ONT to your router. If you do this, you will need to call VZ and have them switch your WAN provisioning from coax to cat5.