On October 2, 2026, Zaptec identified an issue affecting a subset of OCPP Cloud chargers. The issue caused delays in message processing between cloud services, which led to some charging sessions stopping shortly after they began. The incident primarily affected customers using OCPP Cloud integrations. The issue was investigated by the on-call engineering team and was resolved once cloud message-processing latency returned to normal.
## Customer Impact
Some customers experienced interrupted charging sessions for OCPP Cloud chargers.
The main symptoms were
- Charging sessions started from an app stopped shortly after beginning.
- Some sessions ended after delivering little or no energy.
- Affected sessions were not able to continue normally once the backend transaction response was rejected.
Based on the initial customer report, the issue may have affected a significant number of sessions from October 1 to October 2, 2026.
## Timeline
- October 2, 2026, 19:46: Support escalated a customer-reported issue involving OCPP Cloud chargers.
- October 2, 2026, 20:03: The on-call engineer began investigating the issue.
- October 2, 2026, 20:09: Monitoring showed increased delay in message handling between cloud services. This indicated that the issue was likely related to delayed processing rather than charger behavior.
- October 2, 2026, 20:15: Further investigation confirmed unusually high message-processing latency in one of the cloud messaging components. This caused downstream services to process charging events more slowly than normal.
- October 2, 2026, 20:20: Support was informed that a customer-facing status update should be prepared, communicating that Zaptec was experiencing delays in message processing due to cloud infrastructure issues.
- October 2, 2026, 20:22: The engineering team agreed to attempt a mitigation by resizing the affected messaging component in order to move processing to healthier infrastructure.
- October 2, 2026, 20:24: The mitigation was performed, but it did not immediately improve the situation.
- October 2, 2026, 20:26: The on-call engineer began escalating the issue through the cloud infrastructure support path.
- October 2, 2026, 20:48: Message-processing latency returned to normal, and charging-related messages were again being processed as expected.
- October 2, 2026, 21:13: The cloud support partner confirmed that a ticket was being created for further investigation by the underlying cloud provider.
## Root Cause Analysis
The issue was caused by elevated latency in a cloud message-processing component used by Zaptec's backend services.
This delay affected the flow of charging-session messages between systems. As a result, transaction-related messages were not processed within the expected time window. For affected OCPP Cloud sessions, this could cause the backend response to arrive too late or result in the transaction being rejected, after which the charger stopped the session.
The investigation found no indication that the chargers themselves were behaving incorrectly. The chargers followed the expected behavior after receiving a response that the transaction was not accepted.
The issue was also not caused by general database saturation or a broad platform outage. The impact was isolated to the delayed message-processing path used by the affected charging-session flow.
## Resolution
The incident was resolved when the delayed cloud message-processing returned to normal operation at approximately 20:48 on October 2, 2026. An attempted infrastructure resize did not have an immediate observable effect. The issue normalized shortly afterward, and the support path with the cloud infrastructure provider was used to request further investigation.
## Current Status
The affected message-processing path is currently operating normally.
Zaptec has requested further investigation from the relevant infrastructure support channels to determine why the latency increased and whether additional preventive measures are needed.
## Follow-Up Actions
Zaptec will take the following actions: