A man whose pension savings went into unregulated funds says he was offered £6,000 by his financial adviser not to raise concerns with the authorities.
Stephen Sefton, from Milton Keynes, found out his adviser is not authorised to deal with pension transfers.
He was asked not to communicate with journalists, regulators and the national fraud reporting centre, Action Fraud, in return for the money.
The financial adviser said the payment was a "gesture of goodwill".
The adviser also maintains the firm had all the necessary permissions.
Mr Sefton had decided to transfer the £415,000 in his company pension scheme into a new pension in 2015.
He was taking advantage of new pension rules allowing him to access his money as and when he liked, while also leaving some to his children.
Overseas pension scheme
The financial adviser he found online recommended the money should go into an overseas pension scheme.
Mr Sefton agreed, but a year later he became concerned.
Most of his money had been invested through the overseas pension scheme into a fund called Blackmore Global. The rest had gone into an investment fund in Malta.
He struggled to get a proper valuation of what his stake in the Maltese fund was worth, so called the City regulator, the Financial Conduct Authority (FCA).
"They told me the adviser was unregulated to give investment advice," Mr Sefton said.
He was surprised because the company's FCA registration number was displayed at the bottom of the letters it had sent him and the company, Square Mile International Financial based in Prague (and which should not be confused with any company with a similar name), is listed on the FCA register.
But the FCA has confirmed to the BBC that the company was only authorised to deal with insurance mediation. It did not have the necessary permission to deal with pension transfers.
Mr Sefton discovered the fund in Malta was a professional investor fund only and was not suitable for a retail investor like him.
He also found that another company involved in the administrative side of transferring his pension was run by the same men who control Blackmore Global, the unregulated fund where most of his money ended up.
'No strings attached'
After months pursuing his case, Mr Sefton got most of his money back.
Then an email from Square Mile International Financial offered him £6,000 if he signed a confidential settlement agreement.
It required him not to make further communications with anyone about his case and that included journalists, blogs, financial advisers, regulatory authorities and Action Fraud.
He was not impressed.
"I actually believed I had a right to restitution with no conditions, no strings attached, no signing anything that says you're going to shut up and not talk to anyone," he said. "So no, I didn't sign it. I told them in no uncertain terms what they could do with it."
David Vilka, who acted as Mr Sefton's financial adviser and is one of Square Mile International Financial's directors, denies the money was to keep him quiet and said it was a "gesture of goodwill" to close the matter "amicably" after Mr Sefton had made what Mr Vilka describes as "defamatory" remarks.
Mr Vilka said Square Mile International Financial's permissions and activities had been "inspected and verified in full by numerous regulators" and maintains that his firm is authorised and has not done anything wrong.
Mr Sefton did report some of his concerns to Action Fraud, but it wrote to him saying it had not identified any leads to follow up.
He said he had still lost about £30,000 as his stake in the Maltese fund had dropped in value by the time his money was taken out.
His investment in the Blackmore Global fund was returned to him and exit fees were waived.
Other people who have had second thoughts about their Blackmore Global investments are finding it difficult to recover their money.
"Paul" (not his real name) agreed to have his £100,000 pension savings moved into the Blackmore Global fund after, he said, he was cold-called by another company called Aspinal Chase who offered him a free pension review.
He did not know that Aspinal Chase's directors also control Blackmore Global.
Phillip Nunn and Patrick McCreesh are listed as Blackmore Global's directors in a fund document seen by Radio 4's You & Yours programme, which shows they each earn salaries of £20,000 a year.
Investments are locked in for 10 years - a fact which escaped Paul even though it was mentioned in some of his paperwork.
That will take him way beyond his 60th birthday - the age at which he says he wanted to retire. To date, attempts to access his cash have proved unsuccessful.
Even after the 10-year investment period is up, getting money out might not be straightforward as it depends upon the fund being able to find buyers for its underlying assets.
"I've got three grandchildren. I'd like to take them all to Disneyworld in America," said Paul. "I want to spend the money I've earned over the years. A bit of that money would pay off the last bit of my mortgage, so that is a big chunk of my future. I feel as though I've let the family down."
Paul's financial adviser was listed as David Vilka, from Square Mile International Financial, the same man Mr Sefton used, and who also acted for Jacqueline from Oxfordshire.
Jacqueline, who did not want to be identified, said she was also persuaded to move her pension savings after first being cold-called by Aspinal Chase.
Blackmore Global's directors have since refused to release the £50,000 she invested.
Phillip Nunn and Patrick McCreesh said they only allowed redemptions in exceptional circumstances to "protect the integrity of the investment for its other stakeholders".
They said they had no financial relationship with David Vilka or Square Mile International Financial and that they were completely independent from them.
They said their other company - Aspinal Chase - never engaged in cold-calling, did not give pensions advice and that any advice was given by separate, regulated financial advisers.