Hi All,
This is fixed.
It was a setup error for the prepayment side.
The PO is 100% prepayment.
And what the system does is that the tax itself, was added another tax(5% on top of the tax alone) because the prepaid inventory in the Chart of accounts is under the TAXABLE Tax Group Code.
We changed it to NONTAXABLE and it was good to go.
Thanks everyone for the help!