U-Verse fails every day...

We have 3 TVs:  living room, basement, upstairs bedroom.   The router/modem/Gateway is in the basement and has been there for the last 7 or 8 years.  The TV in the living room works pretty consistently -- some pixelation, some unknown pauses, but liveable...    The upstairs TV and the basement TV CONSTANTLY have signal problems -- restart, reboot, uplug, pray, go into the basement and reboot/restart the Gateway, go online to restart the Gateway -- it's a constant, enormous lack of TV reception on the upstairs TV and the basement TV.  How do we call a technician?  How do we resolve this?  I spent 2 hours today on the matter upstairs, unplugging, rebooting, restarting, unplugging, etc.    I'm afraid to buy a new Gateway online because I don't know how to set it up.