Googled and found the "hard reset" options for the router, but thought I'd try here before doing that.
I don't know if this is related, but a few years ago, I "hard reset" a router, and everything stopped working. Although, the PC direct to the modem worked fine.
The issue was the MAC address. The ISP expects the PC MAC address, and I guess I am supposed to report any changes. In the end, I configured the router to use the PC MAC address, and everything work again.
Henry
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