I have had my VR900 for about 2 years now and it's degraded to the point of utter frustration.

Symptoms:

Devices drop offline occasionally.   Like some radom device will no longer connect to the access point.  Reboot the access point, everthing works for a day or two then devices start dropping off again.

Some devices that are connected and sending data every 5 seconds, seem to get ignored and data only shows up every minute or less often.

Left alone for a month the Wifi will lock up completely and drop all devices off while the Internet and wired LAN still work.

The router is running HOT, like close to 50*C on the surface of the case.

It has roughly 25 devices attached.  Most are small smart home style devices.

The DHCP - connected Wireless clients list is completely bogus now, it barely shows half of the devices it issued IP Addresses to.

These problems seem to be gettnig worse and wores over the past 6 months.  I don't need to look to gather it's probably jus tout of warranty.

Also.  How do I turn off the security liabilty such as open public UPNP NOTIFY?

I suspect unless I find a solution to this TP-Link will no longer be a valid networking gear brand I'll buy again.