Price Lock vs discount lock Guarantee

Hello, 

I am wondering how this "24 months price lock" thing from COX is working out for you all. So i just moved my service to a new location (same area) but my bill went up $ 20 higher. I had "Price Lock Guarantee" from COX with 24- months Contract and still under contract but my first bill went up from $108 to $ 128. Spoke to Customer service, they are saying that the price lock doesn't cover any discounts i was getting. I am not sure how can you call that "price lock" when you can raise the bill to take off the discounts anytime you want. 

Anybody been to this situation, wanna chime in?? 

Thanks