Except as otherwise provided by Kan. Stat. Ann. §§ 40-447, 40-3110 and 44-512a, and amendments thereto, each insurance company, fraternal benefit society and any reciprocal or interinsurance exchange licensed to transact the business of insurance in this state which fails or refuses to pay any amount due under any contract of insurance within the time prescribed herein shall pay interest on the amount due. If payment is to be made to the claimant and the same is not paid within 30 calendar days after the amount of the payment is agreed to between the claimant and the insurer, interest at the rate of 18% per annum shall be payable from the date of such agreement. If payment is to be made to any other person for providing repair or other services to the claimant and the same is not paid within 30 calendar days following the date of completion of such services and receipt of the billing statement, interest at the rate of 18% per annum shall be payable on the amount agreed to between the claimant and the insurer from the date of receipt of the billing statement.