Internet Keeps Going Out

Hello - I have used Xfinity for 4+ years and recently, my internet stops working throughout the day. I have recently upgraded my speeds and it is still happening. I then sit there for a minute or two and it begins working again even though I haven't done anything (turn off my computer, restart my modem, etc.). This is happening more and more frequently -help!! I am considering changing internet providers if this isn't solved ASAP as it's impacting my work.