Chaotic confusion

Recently, I found out that Cox Premier Internet is suppose to provide internet speed around 50 mbps (100 mbps soon thanks to the free double speed policy thing).

I've been on this service for 2 years now but I never saw the speed going past  ~35 mbps.

I tried various ways to rule out possible causes for the slow speed (using wired, plugging in only 1 computer, reset router, change router settings. etc..) with no success.

I finally contacted Cox by the chat support and after first representative couldn't find the solution, she created a ticket so the higher tier tech support could take a look at it and told me to check back later to see their answer.

After 24 hrs; representative told me there isn't a response yet.

On the second day, I again contacted cox through chatting and the representative told me that they couldn't see the cause of slow speed from their end either, so they will be sending a technician to check a wiring.

Meanwhile, she noticed that I have an exceeded my data plan this month and started to sound as if I sold dope to a 10 year old (500gb out of 300gb; I discovered torrenting recently. Still, it's ridiculous compared to other competitors like Verizon Fios which has no cap to begin with)

She said that by using excessive data, my speed will be slowed down and the modem and my network adapter will break down.

(Funny because she suggested upgrading to ultimate plan. So that means if I pay more, the very same modem and my computer's adapter that were about to break down will some how work flawlessly?)

I tried to remain polite and went on to ask for other possible explanations.

She stubbornly insisted that the overage caused the slow speed.

I then told her this is my first month that I exceeded my data plan and proceeded to tell her that speed was never above 35mbps all through out, not just this month.

Then, she blamed my modem.

I asked her if I go get a new modem will I be seeing internet speed around 50mbps as promised?

She still mentioned about the overage, saying that even if I get a new modem, speed will be slow until the cycle is finished.

I asked her precisely "So Cox does throttle internet speed if I exceed my data plan?"

Her answer was "Yes"

I told her that on the Cox website, it says Cox doesn't throttle internet speed even if data plan is exceeded.

Then she started giving out nonsense responses, so I finally gave up and closed the chat window.

Still, to this moment, internet speed remains the same.

My questions are:

- Does Cox throttle internet speed or did the representative lie to me?

- If Cox does not throttle internet speed, what is hindering my internet speed from reaching as high as it should be?

I honestly was super excited about internet speed upgrade to 100mbps soon but I doubt it when I'm struggling to get it past 35 mbps.