How to reverse tran 1 Excess ITC

As availed and not yet utilised can reverse in GSTR 3B- in 4B(II)

We claimed excess credit of 10,000/- in TRAN-1 in July 2017. When we realized, we paid the excess payment to VAT department in February 2018 as told to us by GST officer. Now the new GST officer has send us a notice that the payment should be made on GST portal. So the payment of 10,000/- should be paid with interest for 6 years and the previously paid amount under VAT head should be claimed for refund as per the officer. Please guide us what to do. Thanks.