When complaint has been made to the commission concerning any rate, fare or charge for any service performed by any air carrier, and the commission has found, after investigation, that the air carrier has charged an unreasonable, excessive or discriminatory amount for such service, in violation of any of the provisions of this chapter, the commission may order that the air carrier make due reparation to the complainer therefor, with reasonable interest from the date of collection, provided no discrimination will result for such reparation. Such complaint shall be filed with the commission within two years from the time the cause of action accrues and not after; provided, that if a claim based on an overcharge has been presented to the air carrier within the two-year period of limitation, said period shall be extended to include six months from the time notice in writing is given by the air carrier to the claimant of disallowance of the claim, or any part or parts thereof, specified in the notice. If an air carrier does not comply with an order for the payment of money within the time limit in such order, the complainant or any person for whose benefit such order was made, suit may be instituted in any court of competent jurisdiction to recover the same within one year from the date of the order and not after.