Printer not showing in Devices tab of the app.

So I have the T-Mobile 5G gateway serving internet and wi-fi in my house.  Today I connected my printer to the wi-fi network and it works fine, can print from my devices via the wi-fi network, all is well.  But I open the T-Mobile Internet app on my phone and look at the devices in the "Manage devices" tab, and the printer is not listed.  Why?  Is there a limit to how many devices will be listed? (I have 6 listed).