An in-state natural gas pipeline carrier shall file with the commission a written appointment of a named permanent resident, which may be a corporation, of this state as its registered agent in this state on whom service of all notices, regulations, and requests of the commission may be made. The appointment shall specify the address in this state of the appointed agent. The address may be changed from time to time by filing a new address in the state with the commission. If an in-state natural gas pipeline carrier fails to appoint a registered agent, service of notices, regulations, and requests may be made by posting a copy in the main office of the commission and filing a copy in the office of the lieutenant governor.