HDMI 1 no signal with ATT uverse on LG tv

I returned from being away to find all my recordings gone and HDMI 1 showing no signal, The HDMI 1 problem

occurred on one of 3 tv’s. All 4 sets lost recordings.

I rebooted the ATT modem and still had the HDMI 1 no signal on the one tv.

ATT replaced the set top box to the problem tv. 
I unplugged the set top box as well as the problem tv and still the same no signal after plugging back in.

This tv is wall mounted and I cannot get to the HDMI 1 inputs.

Any thoughts.