The balance is usually not the issue: payments get declined by bank limits, anti-fraud checks, a typo in the card details, an expired checkout session or restrictions on the transaction type. Only the issuing bank knows the exact reason — the merchant sees just a broad category.
Common causes
- Limits. The card has a daily or per-transaction limit on online payments, sometimes set by the customer themselves.
- Anti-fraud. An unusual amount, a new country, an odd hour — the bank plays safe.
- Wrong details. An incorrect expiry date or CVC, a typo in the number.
- Expired session. The customer opened the form and confirmed 20 minutes later.
- Transaction restrictions. Some cards are closed to online payments or particular categories.
- A problem at the bank. A failure or an unavailable authentication service.
What the merchant sees
Banks do not disclose decline details — that is protection against card testing. The merchant only receives a category: insufficient funds, issuer decline, invalid data. Build your support flow around those, not guesses.
How it looks at MulenPay
A declined operation stays in the dashboard with the Error status; with a REST API integration the status change arrives as a webhook. A single operation in MulenPay is between 10 and 300,000 roubles.
Example: a bank declines a 45,000 rouble electronics order under a daily limit. In the dashboard the operation is marked Error. The customer pays again via SBP, confirms it in their banking app, and the order is paid without a call to support.
What to fix on your side
- Show a human-readable decline message and offer another method — SBP or a payment link.
- Do not clear the cart: the customer should return to checkout in one click.
- Watch session length: the longer the checkout, the more expired transactions.
- Never show raw error codes instead of plain text.
What to tell the customer
Only the issuing bank knows the exact reason. The customer should check their online payment limits in the banking app and contact the bank. The merchant cannot resolve it, but can offer another way to pay.
Statuses at MulenPay are described on accepting payments; see also the 3-D Secure answer and what is anti-fraud.
