Internet Bill Increase by $30

Hi, my internet bill increased this month by almost $30 for seemingly no reason!? I looked around on the forums and got the idea that some promotional discount ended, but when I looked for lower plans they cost more since I apparently still have the discount. Can someone help me with this? I also don't remember choosing 500 mbps speeds when I originally signed up and would be happy to go with a lower speed plan that matched my previous bill.