ITC Issue in case of Acqusition of Company in Insolvency - Goods and Services Tax - GST

Dear Experts, Our Client has acquired a Company from Resoultion Professional (RP) through Auction on going concern basis. As per NCLT order new management will not be responsible for any Government dues before 01.08.2023 i.e. date of sale certificate. Now GST official has conducted Survey on our company asking issue related to fake ITC pertaining to FY 2018-19 and FY 2019-20 i.e. prior to acquisition. The above issue of Fake ITC was not known as on date of acqusition as per Financial given by RP as on 01.08.2023 The department has never filed any claim before RP for their demand in this regard. Please suggest/guide how to proceeds with and reply Notices/Summon received during Survey.