And here another user with the same problem in V3. It is really deceiving this days to have a repeater which needs a daily reboot to work properly. When can we expect a fixed firmware ? meanwhile I am using a much slower but more stable (and cheaper) netgear repeater. 

@Solla-topee 

May I know the model number of your home router? ASUS RT-AC1200

When the 5Ghz disconnected, would the 5Ghz light still lit up? No, it is not lit

And when you connected to the 5ghz when it loses the connection, what would be the IP address and default gateway on the device?

@Pol88 Has anyone had a successful resolution to this issue ? I'm having exact same issues

The same problem for RE305 and for Archer C5 (in repeater mode). 

After reboot, it is working and 5 minutes later it just stops working.

@TP-Link is there a firmware update for Re450?? 

Having the EXACT same issue with 2 RE450s (v2.0); sometimes it's just one, this morning it was both of them. 2.4 GHz stays connected; thank goodness as that's the majority of our wireless devices. I have updated both to the latest firmware (1.0.5 Build 20200914 Rel. 34203). Our router/gateway is an ARRIS TG3482G (Comcast/Xfinity). Am ONLY using the TP-Links as extenders; not using them for DHCP. In fact, I have found that giving them a static IP address from the main router has addressed performance issues when our local internet service gets interrupted.

The current channel for 5Ghz is 157 and bandwidth is 20/40/80. Has anyone found that changing the router channel for 5GHz has helped?

I have the same, I have RE450 v2.0 1.0.4 Build 20171220 Rel. 73615

I think it might be an issue with channels.

Even though I set 5G channel to 128 or higher, i can see in WiFi analyzer, that the channel is in most congested spectrum of 40-50 - which is the most congested spectrum in most areas. As people tend to leave channels to auto etc.

@Pol88 

i have the same problem. Is there a solution for this?