Mastercard 4834 — Point-of-Interaction Error
Processing Error chargeback.
Code
4834 MastercardCategory
Processing Error
What it means
Processing errors such as duplicate transaction, wrong amount, wrong currency, or late presentment. Includes former 4831.
Evidence that wins
Proof the transaction was processed correctly / separate purchases.
How to prevent it
Idempotency, correct amounts and currency.
Rules and deadlines differ by region and acquirer — always check the instructions in your PSP dashboard.