My Family Mobile Lack of customer support, poor coverage Nationwide

 I just got off the phone with the "customer relations" department at Walmart's My Family Mobile (by T-mobile). It was a totally useless call (2 calls in fact)
The issue, is billing. I cancelled, my service with them in mid-June. I received a bill for July and today I received a bill for August. I will be paying neither. I called to talk to someone about this and all I could get was the the statement that my bill is overdue. The representative was nothing more than a barely understandable human parrot. And that I would have to talk to someone in a different department. I asked to be connected to that department and I was told they can not be contacted by phone. I would have to go to the website. Where the only options were to reconnect with them, or pay the bill. No options to provide feed back or address a problem. I called back this time I got someone who spoke English but she would only repeat the same scripted answer as the first one, the only difference was that I could understand her. After about 15 minutes of this call I finally got an e-mail address. Which I will use. Does it strike anyone else as ironic that a phone company does not do business by phone?
Now for the reasons I cancelled; This price for unlimited talk, text and date is great. The service is good unless you want to make a call or send a text, 411 service is not available. I could sometimes make a call but often if I got as much as 5 miles from home there is no available signal, in town I could have a strong signal and move to the other end of a parking lot and have no signal. If you travel into Iowa or Missouri or Western Illinois service is none existent. I even had one occasion to make a 911 call and could not get a connection at all. I have since switched to Verizon and I am having none of the issues I had with The T-mobile MyFamilyMobile plan.
I do, when I happen to be at Wally World and over hear someone getting or looking at the plan, warn them loudly about it. I have gotten some scowls from the employees. But, Oh well, if they are going to sell crap then they should expect that.