Reverse of Input tax credit

sir i have taken 33000 input tax credit in gst3b return of January 2018 .... but this bill was October 2018 ..... i have filed upto may 2018 return , and i have showing 19000 in gst portal as credit ledger, sir i want to reverse 19000 in gst3b return of june and want to pay 24% interest on it ...... and balance 14000 i want to reverse in October with 24% interest, is this fair? plz tell me also whether i have any other tax liability or have i reduce my outward tax liability???