Slow Internet

I'm paying $118 a month for Extreme Pro Internet.  Since last week my internet speed has been a lot slower.  I work from home and use the internet from 6:30 until 2pm which should be in lower internet traffic time period.  I have tried disconnecting internet cable and restarting but it goes back to slower internet.  I have had an IT specialist come to my house to check out my

computer and connection equipment and contacted my work IT specialist regarding the remote connection.  I have been told it's not my equipment or the work's remote connection.

Why am I having this issue?