Thanks for reaching out to us to let us know what's going on. We always appreciate hearing from our customers and want to clear up anything we can because we want mobile to be simple. There seemed to be some sort of miscommunication at some point because we do not use the same network as Cricket (they are owned by AT&T). This is why you are not receiving the same coverage as you were before. Towers get upgraded by our network partner all the time but if you are experiencing poor coverage we may not be the best fit for you.
As for the bill I can't talk about yours specifically in an open forum like this but if you were to contact our customer support they could open your account and take a look to see what is going on and why phones were disconnected. I can say if you have heavy usage though we might not be the best fit. We're upfront about our rates and do offer a soft cap on data to prevent extreme bill shock (the cap is at 5GB). We want to put people in control of their phone bill which is why we offer usage alerts to be created by the customer, they can be set to help control costs and manage what is being used but it sounds like an unlimited plan may be a better fit for you which is something we don't offer at the moment.