@rfagin 

Power outages can cause the router to reset its settings. Are there known random outages, and is the router plugged directly into an outlet?

It would be best to reflash the latest firmware or update the firmware even though it already has the latest.

Should the router continue to reset it would be best to contact our support at that point.

There have been no power outages. The router is plugged directly into an outlet.  The most recent reset took place while working on my desktop machine and was discovered when trying to print a document.  The firmware was recently upgraded as suggested in response to three previous self-resets.  If relevant, the self-reset problem started after the router was converted to use as a wireless AP.  When used as a router, the self-reset did not happen, and the router has been in continuous service for about two years.