Netgear XR500 seems dead - help

My XR500 on 23.05.3 has been running fine for 4 months, but last month it stopped working.
I set it up to restart once a week, on Sunday mornings.
I awoke one Sunday to no internet and had to swap out the XR500 for another router.
There was no power LED light showing - not white or yellow or red.
I reset via the reset pin access - no change.
I held reset down and powered it up - no change.
I left it alone for a week - no change.
Searching online, it appears to be a hardware failure.
Does anyone here have any ideas of how to get it going?

Tried replacing the power adapter?

yes, the networking lights on the right still flash up, but only one of them - usb i think - stays on.