Upload speed less than 1/2 of what it should

Last week I got xfinity internet. The plan I got was 1gb down and 110mb up. I am only getting 40mb up. I am using the xb8-t modem. Why is this not giving me my full upload speed? I actually need my upload speed as I self host. I have my own cloud from my home that works through my internet so upload speed is incredibly important. I have rebooted the modem, everything i can think of. This is becoming very annoying