Okla. Admin. Code § 260:50-3-7
When premiums are underpaid for coverage which has been selected and provided, future payments will first be applied to the shortage and the shortage will be rolled forward. Employees may not choose to retroactively cancel coverage that was selected. The full amount of the underpaid premium shall be submitted within sixty [60] days after the date EGID notifies the insured or the insured's employer of the error. When the underpayment occurs because an employee has entered into a salary reduction agreement pursuant to the Internal Revenue Code, and the insured's employer has erroneously failed to withhold and submit the proper premiums to EGID, the insured's employer shall be solely responsible for the payment of outstanding underpaid premiums to EGID. Failure to submit premiums could result in loss of coverage in accordance with 260:50-3-5(a)(3).
Okla. Admin. Code § 260:50-3-7