Postmortem: # Overview

The inbound Confirmation of Payee (COP) service experienced slower‑than‑expected processing of account updates. While core COP checks continued to operate normally, some newly created accounts took longer to appear in the directory service of an external partner, which could affect matching availability for some customers. Normal processing has since been fully restored, and the backlog of updates has cleared.

Client Impact

New accounts took longer than expected to appear in the external partner directory. Some sub‑accounts were also delayed in being registered. Existing accounts were not affected and continued to receive expected COP match responses. Core COP request/response behaviour remained within expected performance levels.

Root Cause

The delays occurred because the COP inbound service received a higher‑than‑usual volume of account updates over a short period. These updates are sent to an external partner’s directory service, which applies standard processing limits to ensure stability. The temporary increase in traffic exceeded those limits, leading to a queue of updates waiting to be processed. As a result, some newly created accounts took longer than usual to appear in the directory. Once the update volume naturally returned to normal levels, the queue cleared and processing performance stabilised without further action required.

Resolved: The issue impacting the Confirmation of Payee (CoP) inbound service has been resolved, and service was fully restored to business as usual from 5:30pm (UK time) yesterday.

Our engineering team has implemented a fix and continues to monitor the service to ensure ongoing stability.

We apologise for any inconvenience caused and thank you for your patience.

Investigating: We are currently investigating delays within the Confirmation of Payee (COP) inbound service.

Our engineering team is actively working to identify and resolve the issue as quickly as possible.

We will provide further updates as soon as more information becomes available.

We appreciate your patience while we work to resolve this.