Last month, the Guardian investigated when dozens of residents complained about a barrage of unsolicited calls from a company claiming they could claw back thousands of pounds in personal banking charges.

Now, officers from Lancashire's Trading Standards and Lancashire County Council are warning residents to be careful after they received more than 50 complaints about the same firm - which they named as CMS or Credit Management Systems.

County Coun Marcus Johnstone, Cabinet member for community, planning and partnerships, said: "Whilst we believe this particular business is not seeking to misuse any information, we would always advise consumers never to respond to unsolicited emails, letters or telephone calls asking for bank or credit card details."

The company provides an address of either Swansea or Port Talbot in West Glamorgan, Wales.

Their representatives usually speak with foreign accents and ask for £49.99 to claim back bank charges from the past five years. To do this they ask residents for sensitive information, such as bank details.

Chief Trading Standards Officer, Jim Potts, said: "The Ministry of Justice has responsibility under The Compensation Act 2006 for the regulation of claims management activities.

"Under this law such businesses must be authorised by the Ministry of Justice and offences occur when companies provide claims management services without authorisation.

"Although Credit Management Systems is authorised by the Ministry of Justice, we are concerned about their selling methods and we are contacting the Trading Standards Service where the business is based to express our concerns at their sales techniques and will take the matter up with the Office of Fair Trading and Ministry of Justice if appropriate."

The Consumer Champion spoke to an employee at Swansea-based Credit Management System.

He said they hadn't received any complaints and asked the Champ to speak to his manager.

Unfortunately the number was permanently engaged.