Slow WiFi with Gigabit and Eero 6e Pro

I just recently setup a three pack of Eero 6e Pros. When I am standing near my gateway and run a speed test on my phone, I get speeds around 800 down 40 up, but when I walk 20 paces away, the speeds drop to sometimes less than 4 down and 1 up. I am not going so far away that the gateway should be that far out of range. When I disconnect from the WiFi and reconnect, it links me to a different Eero, but I am still only getting around 80 down and 40 up. My house is only 2800 sq ft, with a router on all three levels in different zones of the house. I should not have any dead zones like that. Any suggestions to resolve slow speed?