@cmyachtie 

Just adding some background info that may help, before I purchased the new TP-LINK router last year to get better security from my 10 yr old Linksys, the new wifi 6 did everything right, AirPrint from my IOS devices to my Canon MG6320, Windows laptop etc. and showed all devices in the client list and I kept my Linksys for my guest wifi use.

A couple of days ago I had to use my Canon printer just to print a photo(which my other HP printer can't), and my workaround is to hook my Canon AI1 printer & iPhone onto the guest router WIFI and job success!........which sucks but it works for me, allbeit unhappyly!

My setup is Bell FIBE1 Modem where both my routers are connected to.

  @Carl 

Decided to try something else and changed the wireless security settings of my TP-LINK router back to WPA2(which what my old LINKSYS router was) from the WPA3 default settings of my new router, (reason I went for a new router a year ago was cause the newer WPA3).

And it all worked for almost a year happily together until Apple came out with IOS 17.

And now my old CANON MG6320 is printing again over AirPrint!!

Also is showing up in my router connection list and is still connected and able to print to after changing my router security settings back to the higher WPE3 security.

Fingers crossed it stays there longer than a day or so.....!

All in all it appears to me that there is some backwards compatibility lacking issues with both the newer wireless security protocols and Apple IOS 17 updates causing me all this misery. All this seems to force us to buy newer devices unnecessarily.

Forgot to mention that despite all that above my client list only shows roughly half of my devices on my router network, some older and even the latest new devices don’t show up on the client list recently. 
I have a total of 21 devices and 9 showing.
Everything was listed until about last summer.

  @CactusJack same issue with Archer AX3000 in access point mode.