Sounds like you need to enable 802.1r for fast roaming between APs on both access points and then make sure the SSIDs are the same.

Also, you can improve things by splitting your 2.4ghz, 5ghz, and 6ghz (if applicable) onto separate SSIDs, with your phone connected to the 5ghz band. Since it has lower range, it will likely roam better because the signal from one to the other will be more "apparent" to your devices.

WiFi continually beacons out to try and find previously connected networks and will select for the best signal from an AP it can reach. Extenders can be a trick if you're sitting in the 'crossover' space between the extender and the back haul it connects to.

What you might try instead is one of those distributed AP systems like Unifi or similar where all the APs are controlled by a switch and work in unison. The one I have at least has an ability to disconnect someone if they drop below a certain level and migrate them to another AP without breaking the session states.

The other option that I can think of is just turning off the auto connect for the extender net and only using that manually.

So this generally happens because there's too much overlap between the APs, try reducing transmit power on the 2.4ghz radio on the extender.

Also making sure that fast roaming is enabled on both APs should help.

You can also try enabling minimum RSSI on the extender 2.4ghz radio if it supports that.

I totally agree we should have the ability to tell it what to use, and it should make a concerted effort to those in order.

Funny how many responses you’re getting to the effect of explaining why your phone is doing what it’s doing, which is not at all what you asked. People feel the absolute need to spew, regardless of whether they actually have anything to contribute. Or, they’re bots guessing at what you wanted lol.

So okay all the must-say-somethings, shoot your load and leave lol. We’ll be sure to downvote appropriately. The standard routine continues.

Usually this is handled by the access points. If you're running dual band (2.4GHz and 5GHz) you will get worse strength out of 5, typically, since it doesn't go as far or penetrate as well as 2.4. The access points will try to kick a client to another, better quality access point if they're smart enough. This is generally how business access points work. You might want to see if whatever ones you're using support this. Also it's best if they are both the same SSID, in case they are not.

Wtf I have exactly the same problem. Right down to the security cameras. Lol

Afaik this is a host "problem", not client. If you have a Asus mesh, you can set some rssi level at when the host will disconnect the client so the client will connect on the other AP.

Else the client will happily stay on the weaker host. On

With Unifi APs you can set the minimum RSI on the individual devices which makes them kick the device off and then the device will generally attempt to connect to the AP with the best signal. This is an advanced setup and some devices might not like getting kicked off though.

If the extender has a different SSID, you can disable auto connect for that access point.