KS Stat §40-2442(f)

(f) In the event that an insurer erroneously pays a claim providing benefits to which the insured person or provider is not entitled, the insurer shall not initiate a request for reimbursement or refund of that erroneous payment, or in any other way seek to recoup the erroneous payment, unless such action is initiated within 18 months after the end of the month in which the erroneous payment was made.