5G Home Internet Suddenly Very Unstable And Technical Support Is Essentially Useless

I've had the exact same experience in Virginia, with speeds dropping to low single digits over the last 3 months, after being good for over a year. And always the same excuse from tech support as others have said- they blamed it on tower upgrades and promised improvement when completed. I upgraded from the Nokia to the Arcadyan gateway but that made no difference, except the Arcadyan gets a better signal (3 bars vs 2) but speeds are still poor, rarely getting above 10 Mbps. And it never connects to the 5g secondary band, just 4g. In the past I was getting fairly consistent connections to both. Very frustrating as we don't have any other good Internet options here.