CONSUMER COMPLAINTS REGARDING TARIFFS.

(a) This chapter does not restrict: (1) a consumer's right to complain to the commission about the application of an ambiguous tariff; or (2) the commission's right to determine: (A) the proper application of that tariff; or (B) the proper rate if that tariff does not apply. (b) This section does not permit the commission to: (1) lower a tariff rate except as specifically provided by this title; (2) change the commission's interpretation of a tariff; or (3) extend the application of a tariff to a new class of customers.