Whenever it shall come to the knowledge of the commission, either from its own investigation or by complaint made to it in any manner whatsoever, that the rates charged by any public utility including any common carrier on interstate business are unjust or unreasonable or that the rates, rules, or practices of such utility:
1. Discriminate unjustly against the citizens, industries, or interests of this state;
2. Place any of the citizens, industries, or interests of this state at an unreasonable disadvantage as compared with those of other states; or 3. Are levied, laid, or otherwise in violation of federal law, rulings, orders, or regulations, the commission immediately shall call such facts to the attention of the officials of such public utility and urge upon them the propriety of changing such rates, rules, or practices.