If you notice that one WAP is having this issue more than others, replace that WAP.
WiFi range extenders DO THINGS LIKE THIS and our office will NEVER deploy range extenders. They are tar pits and black holes of support. As you do more networking you learn to never use an extender.
Hope this helps.
I have a fibre feeding into a Huawei 965b router (with hidden 2ghz and 5ghz network) feeding a tplink 901d (acting as AP with a 2ghz wifi) in the far end of the house conected POE, the local wireless printer is conected to the tplink as is a tv and users on phones when down there, a Synology NAS is wired to the huewei , there is also a apple air port extreme (2ghz and 5ghz wifi) conected to the Huawei and a wifi range extender extending the apple 2ghz wifi network out to the bus depot, now I needed all devices to be able to access the printer and the nas, I ended up giving all the devices the same ip , eg 192.168.1.* each have there own ip range as in one goes from 192.168.1.10-192.168.1.60 the next device goes from 192.168.1.60-192.168.1.120 ( the device has a static ip as the first number hence 192.168.1.60) that way the device will have the last number from the previous device, all have different ssid and passwords , this way it's one big network , it seems to work however I get the occasional loading circle that never goes away until I change wifi networks , is there an easier way to do this ? It might help if you draw it out on a piece of paper ,

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