"Preauth cannot start because another tap transaction is already active"

Last updated: June 24, 2026

Quick answer

A prior read was interrupted and persisted. Restart the Tap to Ready app or call KoardMerchantSdk.cancelTransaction(), then retry. See Running Payments on Android.

Symptoms

  • Preauth cannot start because another tap transaction is already active

Solution

A prior card read was interrupted and left a session open. Restart the Visa Tap to Ready app or call KoardMerchantSdk.cancelTransaction(), then retry.

Related articles

See also