The error in Brightmere's Nell assistant has moved a familiar supplier question into a new setting: who controls a change that alters what customers are told? The company says a model update was involved in incorrect payment-plan messages issued between 9 and 19 March. It is honouring the advice received by around 1,400 customers.
Brightmere put the cost of its response at about £600,000, including the consequences of honouring the messages and contacting affected households. That is a company estimate rather than a published breakdown of individual cases. The supplier has not released its software contract or the technical incident report to this publication.
Independent software consultant Felix Romsey said an assistant can change in ways that are difficult to see from a screen showing the same name and design. 'The customer still sees Nell,' he said. 'Inside the service, something may have changed in how an answer is generated. Someone has to know that change is coming and decide what to check.'
The supplier said the relevant responses had been reviewed and restrictions applied while the problem was addressed. Asked what notice it had received of the model change, and what testing preceded it, Brightmere said it was examining the incident with its technology provider. It did not disclose the commercial terms governing updates.
Those answers leave several practical questions open. A model can be tested against examples, but payment-plan conversations involve account context as well as wording. Romsey said a test should distinguish between explaining an existing arrangement and appearing to authorise a new one. He did not claim to have examined Nell or Brightmere's customer records.
The incident also concerns the route back to human service. Brightmere advertises access to advisers when Nell cannot resolve a question. Customers who have already received an apparently definite answer may not realise that they need to seek confirmation, particularly where the answer offers relief from an immediate payment concern.
A Brightmere spokesperson said the company remained responsible for the information provided through its channels. The supplier said it was contacting affected customers and would honour the incorrect advice. It did not provide a timetable for publishing a fuller explanation of how future model changes would be checked.
For suppliers considering similar tools, the questions are operational as well as technical: who sees a release notice, who can restrict a category of answer and how does an adviser identify the conversation that led to a disputed promise? Brightmere has answered the immediate question of whether it will stand behind the messages. Further detail about change control remains awaited.