What could cause false 02 sensor codes?

Last year I got a reading the 02 sensor went bad. I changed it. Shortly after the truck started not accelerating. I took it in and the catalytic converter was shot. I replaced it. A day later the codes popped up again for the 02 sensor(s). I took it in to have my tires changed and while it was up in the air, I asked the guy if he could scan my computer again and take a look where the 02 sensor was. He showed me. Whoever put the catalytic converter on at the other shop, melted the harness and 02 sensor. I figured, easy fix. I bought another one. I reset the light and drove about an hour until it came back on, again. Same codes. So, I took it to the first shop whom did the melting of the sensor and wiring harness it plugs into. They said they could not find the harness to purchase so they would have to splice the harness. (Female end) They reset the light and again, an hour later the light came back on. I scanned it and it's the same codes. Something else is triggering it and I'm not sure at what else to look at or test.

I'm not great with vehicles. I can do the basic stuff. One thing though, the codes I'm getting now are for 2 separate sensors. One is a bank one and the other is a bank 2 both being sensor 1. Can that 1 harness give out codes for 2 sensors?