Haw. Rev. Stat. § 88-106
Should any change or error in records result in any member, retirant, or beneficiary receiving from the system more or less than the member, retirant, or beneficiary would have been entitled to receive had the records been correct, the board of trustees shall correct the error and as far as practicable, shall adjust the payments in such a manner that the actuarial equivalent of the benefit to which the member, retirant, or beneficiary was correctly entitled shall be paid. Should any error in calculation or records result in any member, retirant, or beneficiary receiving from the system more than the member, retirant, or beneficiary would have been entitled to receive had the calculation or records been correct, the board of trustees shall correct the error and shall recover any such overpayment unless recovery is waived pursuant to procedures adopted under section 88-6.
HRS § 88-106