Paying for 1000Mbp/s, getting 200

Hi, I've had this issue since I upgraded from 300 to 1gig. At 300 I had max speeds 99% of the time, but since the upgrade I've never even come close to 1 gig, in fact getting less speed than I had before. I've had multiple chats with service reps but eventually gave up. Hoping here I can maybe get a solution. 

I use a wireless adapter that's rated for 1.3Ghz. It's a USB adapter plugged into a USB 3.1 port connected directly to the motherboard.