OnlyKey stopped working. Backup OnlyKey works fine

Have been using my OnlyKey for quite some time now (over a year) without issue. Plugged the OnlyKey into the USB slot and… nothing. No LED light, OnlyKey software did not recognize it, nothing. Plugged in my backup OnlyKey (different device) into the same slot, and the backup device worked fine. Attempted to try the primary OnlyKey device again, but it did not work. The same results were obtained as the original attempt (i.e. No LED light, OnlyKey software did not recognize it, nothing…).

Does anyone have any ideas as to why this happened and/or how to fix it?

The first thing to try is plugging the bad OnlyKey into other ports/computers. If it still does not work at all this sounds like hardware failure.