can't get dvr to connect

I moved from uverse to Direct. Since then we have experienced constant internet connectivity issues. Previously, the uverse Motorola WiFi gateway was attached to the uverse dvr, which is now no longer the case,as no more dvr. The gateway is still connected to the ATT modem. Wondering if this set up can be the cause of the connectivity issues. I’ve read about IP address conflicts. Thanks 

@Leighatx 

Please start a new thread as this is from a few years ago (and for currently having U-Verse where you now have something DirecTV). Clarify if you are a satellite or streaming-only customer and what exact equipment you're trying to connect to your gateway/modem/router