I've had similar issues. For the first 6 months, had no problem with my Sunday subscription, suddenly had to call every month or so to sort something out.
An outside company handles the deliveries. So far, I've had an entire month tacked onto the subscription, and recently asked for money back. At one point, I spoke directly with the delivery person, who apparently gets in trouble when you report a missing paper.
No one is stealing your paper, it's just not being delivered.