Shady billing practices for horrible internet service

So here's the deal I sign up for internet Internet is 50 bucks a month okay but for some reason my bill keeps changing on top of that they keep adding late fees because they say my bill is due before I ever use the service and then they send out an actual bill for the due date before my service is up I have post paid service not prepaid so why am I being pre-built for service and then charge the late fee for not paying my bill on time for service I have not even used yet this is shady as **bleep**.  Then last month there's a return to check payment or fee on my bill I pay through PayPal's bill service and PayPal has never once screwed up my bill pays never once have I had a problem with PayPal matter of fact I've had PayPal help me with other people's problems so for Cox to say that it was a return fee from a payment that I did through PayPal is bull.  On top of that I noticed that I make my payment on Monday it doesn't post to my account till Friday is that so that you can add those late fees what's the deal this is BS my bill should be 52.07 a month never change so how do i owe 78 when last month i paid 83 how is that even possible?