Cannot reach costumer service

Hello, I did my speed check recently I have Fast plan internet so my download speed is correct however my upload speed is only 11mbps and according to my plan it should be a 100. I called 1800 Xfinity and tried to reach the agent after the system restarted my modem, however right before it tries to transfer me to an agent it says that I have reached non working number, is this some sort of glitch? How can I speak with someone on the phone? 

Thanks