RBR40 Router and Satellites are no longer working

Lately, we've been experiencing periodic connectivity issues with devices (e.g. - phones, tablets, laptops, et al.) on our home network.  Today, I decided to try to tackle it.  Waaaay too many hours later, I decided to start from scratch--I disconnected my Orbi router from my modem, unplugged my modem, waited a few minutes, plugged my modem back in, plugged my Orbi back in, connected my modem to my Orbi--and now my desktop pc won't recognize my Orbi network.  Currently, my desktop PC is connected directly to my modem, so I know it's not a modem issue.  What's going on with my Orbi???  When I ran the diagnostics on my Windows PC desktop, it said the DNS was not responding.  I attempted to manually enter a DNS and an alternate DNS according to web guidance, still to no avail.  When my Orbi is connected, the white light flashes slowly.  When I unplug it from the modem, it lights a steady magenta light.  Anybody got any suggestions???