Common FBR Errors — Causes and Fixes

By Arslan Riaz Updated Jun 21, 2026 340 views

Use this reference to quickly identify and resolve FBR submission failures.

Error Reference Table

Error Likely Cause Fix
401 UnauthorizedWrong POS ID or TokenSettings → FBR → correct credentials
Invalid UOM CodeUnit has no FBR codeSettings → Units → add FBR UOM code
PCT Code RequiredProduct missing HS codeEdit product → FBR tab → add HS code
Duplicate InvoiceAlready submitted to FBRCheck FBR Logs for existing FIN; do not retry
NTN MismatchBusiness NTN doesn't match FBR recordsSettings → Business Settings → correct NTN
Timeout / No ResponseFBR servers are temporarily downWait 5–10 min and retry. Check fbr.gov.pk for status.
📌 Note:After fixing the issue, always retry the sync from Sales → List Sales → Actions → Sync with FBR — not by deleting and re-creating the invoice.
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