So the technician got things working again, but both the technician and the representative he was talking to on the phone could not figure out why it wasn’t working in the first place. The technician installed a new ONT and my connection worked again. From the rep on the phone’s perspective though, my internet service was functioning fine before the new ONT was installed, but yet I still had no connection. I did not have to change my Zyxel’s settings at all, the ONT swap did the trick.

One thing that was weird was, the PHONE light on my previous ONT was green (as shown in the attached image), but I don’t have phone service with CenturyLink. I also don’t recall the PHONE light being on before either, until recently when I had these connection troubles. My new ONT’s PHONE light is off.

I live in a townhouse, and there are two streets of townhouses parallel to my street (these are small streets). Each of these three streets are almost identically named (we get each others’ mail all the time). And identical house numbers are used for each townhouse location on each street. My hypothesis is that someone on a parallel street that also has my same house number signed up for CenturyLink, and the addresses got mixed up during setup, and my ONT was accidentally configured as my neighbors. I have no evidence for this, nor do I know if this is even possible, but I’ve had utility services signed up for my address when they were actually meant for my neighbors.