Multiple IP's and Device's going offline

[Kn1ghtRa1der]

I started having issues this morning with my devices going offline and some showing multiple IP's within the Routers software.   I thought this was because before I started seeing this I tried to setup a USB drive to get the Plex server on the router setup.   However, I did a full factory reset, twice, and upgraded the firmware, and did a third factory reset which with the third reset I changed the SSID and Password and went and connected every one of my devices, which are a lot and took hours, to have it only work for about 30 minutes before most of the wifi devices started to lose connection again.   So now I am back to square 1.   Please help asap.   This is a $450 investment that I made because I thought it was worth it and this is now the third issue, this being the worse, that I am having with this device since I bought it May 7 2019.  

[Netduma Fraser]

Usually when a device shows more than one IP it's because it's been connected to both ethernet and WiFi so it tries to combine them as one device rather than showing a second device. Do you notice any disconnects on wired devices at all? Are you using smart connect for WiFi? If you disable this and connect manually to 2.4/5GHz do you get the same issue? Do you see any entries in the System Information logs around the time it happens? How long do the disconnections last for? Do you need to reboot the router to re-establish a connection or does it regain the connection by itself - if so how long does it last for?