Controllers disconnecting and won't enter pairing mode

[mattpag]

So I have been away for a couple of days and I turned off both radiators while away. I came home turned them back on and now both radiators are showing the temperature as they were before but now there is also a blinking white dot.

I managed to get one of them into pairing mode and connect it again to my account. And currently it is now working normally. However, based on previous behaviour I expect this to disconnect within 24 hours. What can I do to stop this controller disconnecting? As a reminder 3 out of 5 are working normally. It is just these two which seems to have a different firmware.

Thank you

[pzygmunt]

First, check if restarting the router helps after disconnecting.

[mattpag]

I have tried that. Unfortunately that doesn't help.

Thanks

[pzygmunt]

After updating, do you see an icon in the app where you can check the WiFi signal strength? When the heater is disconnected, does a dot flash on the display? Do you have multiple access points in your home?

[mattpag]

Yes I see an icon in the app for one of the disconnecting controllers but not the other. I can see the WiFi signal strength. Yes, when the heater is disconnected a dot is flashing on the display. There is only one access point.

[pzygmunt]

What signal strength are you seeing? Can you post a screenshot? If it's disconnected, can you put the device into pairing mode without resetting the power? If so, then put it into pairing mode. Open the website http://192.168.4.1 and check the LAST STATE header. It's best to take a screenshot.