I switched from ATT to verizone and it was a big mistake!! Verizon's data is aweful!!!
My speedtest from both the app and also Google shows 5mgbs download and 0.1 mgbps upload!!!! I used to have 60 mgbs upload and 15 mgbps upload with att. I tried different times of the day, no luck. I even spent more than several hours talking with agents and nothing! The brilliant solution of the agents was to reset and power on and off my phone