Undertaking declaration

We had filled a excess cash refund claim on GST site we had received a queries letter on the following details are more required if you have any certain format please provide us 1) Undertaking that the said refund claim has been filed only before single tax Autority 2) Undertaking to any amount refunded wrongly same will be paid to department along with interest. 3)Undertaking to declared that no other refund claim has been filed by you