Tran-1 credit reversal

vinit (nasik) (56 Points)

17 July 2019  
VAT credit taken through Tran-1.
Such credit been utilised for setting of liability till July 2018.
Later in August 2018 it was identified that the credit of Tran-1 was wrongly taken nd the same was reversed in gstr-3b.
Till today it is not reversed in Tran-1 reversal.
Can such reversal b done in GSTR-9?
If reversed do i have to pay in cash all the credit taken and interest on it?