High-Speed Internet Gateway will not lock to 5G speeds (5G21)

futureray wrote:

Update, this morning I decided just to get the best location for the best signal for the B2 700 Mhz band. Was getting 70 Mbps download and 25 Mbps upload. Said to myself that will fine for now. Then a few hours later, the gateway is on B66 - 5G. But why did I noticed this, the speed was terrible 16/5. So I started playing with the best location for the gateway, I have it hooked to UPS and tried different position in my area where I know 5G works great on my phone. The whole time it locked to 5G. So my initial issue fixed only to read what djb14336 stated by deprioritized on the network. I think he is right.  So even if you are fortunate to get B66, T-Mobile has given this last priority status on the network. I go to test over the weekend, see if it gets any better or worse or loses 5G again. 

What frequency is Band 2 LTE?

Frequency Band of 3GPP LTE FDD mode