Been trying to reach someone about this for awhile, and it is impossible to speak with someone. Internet speeds.

I pay for 500MB down and 20 up. Moved to the area in December, and had to get a whole new wire ran to the apartment due to it being so old ,that process alone took 5 techs to come out to confirm it was needed, and get me internet that semi worked until the new line was installed later. Before the new line was installed, I was getting 1-10 MBS up. After the new line was installed, I was getting the correct amount I am paying for .500MBS down and 20 up. As of Labor day weekend, My internet speeds have been capped at 150 MBS. I figured it might having to do with someone new moving into the apartment and paying for lower speeds, and they accidentally adjusted my cap to theirs. However, earlier this month in October, I called in, after going through the whole process of "troubleshooting" which I already tried, and they told me they were going to fix the issue, and credit my account. They also mentioned others were having issues in the area, and they can send a tech out. I have since never heard back of a resolution and my speeds still are way under what I pay for and drop periodically. How can I either: 

1. Adjust my bill lower to pay for the speeds I am actually getting. 

2. Get the issue resolved so I am getting the speeds I am paying for? 

3. Get ahold of someone to actually talk to people about the issue, who will action my previous request when I called in earlier this month. 

My computer is hardwired in to a router that can go up to 1GB, My modem is also capable of 1GB. 
I have run multiple speed tests on multiple sites, I have reset my router, and modem multiple times, the speeds never go above 150MBS and typically stay around 70-100MBB