@Kevin_Z I set my AX1500 as router and yes it's my only ax router in the house. Well I never really rebooted when I change the setting, I just clicked "Save" and there it was. I'll try and bring you...

@woozle I thought it might be a bug in the firmware or something too, but if it's really a bug TPLINK should update the firmware

I have TP LINK AX 1500 in my house and one day I enabled 5GHz mode to only work with WiFi 6 (ax) protocol and also renamed it so I can differentiate between 5GHz and 2.4GHz SSID. And out of curiosity...