> Sure refuse to pay my cell phone bill and switch to one of the 3 competitors.
Unless it's a massive set of charges, the resulting collections activity and credit score hit will likely cost a lot more than you're saving by ignoring the bill.
"I did not authorize this charge. If you disagree, take me to court."
So they can drop the charge, or they can take you to court. I find my chances fairly good at disputing a charge I did not authorize in front of a judge. I am willing to take that risk.