UPI error code · Account status
UPI error B1: Registered mobile number changed
The mobile number mapped to the bank account was changed or removed, so UPI device binding is invalid.
Apps may show it as: “mobile number changed”, “sim changed”
- Who declined it
- Customer / PIN
- Type
- Account status
- Money debited?
- Usually no debit
- Refund
- No debit
Is money deducted on UPI error B1?
Usually not: B1 is normally declined before the debit. Confirm with your bank SMS or passbook rather than the app tile.
How to fix UPI error B1
Update the mobile number at the bank, then re-register UPI on the new SIM. Old device bindings will keep failing.
Shopkeepers: is B1 a problem with my QR?
Customer-side SIM/KYC issue.
Never release goods on a green screenshot alone. Match the UTR in your bank SMS, ledger or soundbox.
If it keeps failing
- Open the failed payment in the app and copy the 12-digit UTR.
- Use Raise issue or Check status in the app first.
- Then call your bank with the UTR, amount and time. NPCI's UPI helpdesk is 1800-120-1740.
- After 30 days without a fix, complain on the RBI ombudsman portal, cms.rbi.org.in.
Related error codes
Last reviewed 26 August 2026. Meaning based on: PhonePe PG: TXN_NOT_ALLOWED; Zerodha. Apps word codes differently, so if your bank describes B1 another way, trust the bank and keep the UTR.
Sources: PhonePe Payment Gateway error codes · Zerodha NPCI UPI reason codes · RBI TAT for failed UPI (DPSS.CO.PD No.629/02.01.014/2019-20)