The Complaints Commissioner heard how the investor checked the register before buying bonds from a company masquerading as to be a credit union in 2016

The FCA's register showed no cause for concern and said the scam firm was authorised.

But in fact the company had dissolved in 2012, which the FCA knew but had not updated its register because it prioritised making other updates to the list of authorised firms.

Commissioner Antony Townsend upheld the complaint and a published conclusion read: “Consumers have a duty to undertake their own checks to avoid scams: there are many cases of scammers using the names of properly authorised firms to dupe investors, and the FCA cannot be held responsible in such cases.

“Against that, consumers are entitled to expect that the register will be kept competently.

“This was more than a simple oversight.

“The record clearly shows that there was an awareness of the situation, but no effective action was taken until [the] complaint was lodged.

“Worse, the records which I have studied give me no confidence that the responsible departments understand the seriousness of the FCA’s failings.

“While it is understandable that the FCA should be protected from general liability for consumers’ losses, this is not an ordinary case.

“The FCA (and the FSA before it) for some four years sat on information which should have prompted action to remove the credit union from the register.”

Mr Townsend said the FCA were accountable for all the investor’s losses, which were to the tune of £44,275 - but instead should pay half, which was offered by the FCA.

The credit union was dissolved in 2012 but in the intervening four years between then and when the investment was made, a clone firm assumed its identity.

The report added: “Parliament has protected the FCA from claims for ‘lack of care’, and there is no evidence that the FCA acted in bad faith, so I do not think that the FCA is legally liable for [the] loss.

“In the circumstances, I think that the FCA’s offer is reasonable.”

In conclusion Mr Townsend called for the FCA to “review its internal processes to ensure that staff understand the priority which should be given to keeping the register up to date.”