P. U. Code §451 requires: "All charges demanded or received by any public utility, or by any two or more public utilities, for any product or commodity furnished or to be furnished or any service rendered or to be rendered shall be just and reasonable. Every unjust or unreasonable charge demanded or received for such product or commodity or service is unlawful." Americatel's placement of unauthorized charges and overcharging of customers are both widespread and egregious. Americatel unjustly charged customers, in violation of P. U. Code §451.