setff.inTwo files, one month. You’ll see which invoices in your books never made it to the portal, and what that’s worth. The matching runs on this machine — open the network tab and check if you’d rather verify than trust.
From Tally, Busy, or a spreadsheet. Needs supplier GSTIN, invoice number, date, taxable value and tax.
The B2B sheet from your 2B download, saved as CSV. The one you already pull every month.