Well. I gathered up my courage and called Verizon's customer service number. I naturally expected to be put on hold for an hour and a half, but that didn't happen. I conversed only with a machine.
It first asked me if the phone I was calling from was the phone associated with the account, which I found confusing, since my phone service is from AT&T. So I hung up. But then it occurred to me that since it's my only phone, it's number must be the one "associated with my account".
So I called back. Past that hurdle, the machine asked me if I was calling about creating an account, several more possibilities, and "internet service". I said "internet service". The machine--I'll call her "Sally"--then asked if I was unable to connect to the internet. Not wishing to complicate things--after all, I was technically connected, but my computer told me I wasn't--I just said "yes".
What happened next was surprising, at least to me. Sally told me she could see there was a problem, and would try to fix it. She asked me to stay near my computer, adding that it might take a few minutes.
So I brought the computer out of sleep mode, and after about 30 seconds, my connection came back. Sally asked if it had; I said yes. And that was the end of our conversation.
For now. I suppose we'll see later on if it continues to work if I leave the room for awhile and it goes into sleep mode.