Brother printer won't connect to KVD21 Gateway

I have two brother printers and when I initially set up the internet, I couldn't get the printers to connect. I did two things - I split the networks into 2.5 and 5Ghz.  You can do this through the admin panel.  This seemed to work, but the printers would not stay connected to wifi, so instead of letting the computer find and install the printer, I actually keyed in the IP address of each printer.  This worked like a charm.  I might be one of the lucky ones, but tmobile internet is faster and more reliable than Fios.  I still have both and will keep both for a month or so, but so far I couldn't be happier.  I also have no problem with VPN for work.