Users of the exchange, one of the world's biggest, said they were unable to withdraw or deposit sterling via the Faster Payments network - which enables mobile, internet and other payments between British bank accounts - or bank cards.
While standards are widely seen to have improved, global regulators and policymakers have in recent months voiced concerns over the illicit use of crypto.
The Financial Conduct Authority (FCA) said it would have imposed a substantial fine on the company if it had not already been in liquidation or owed its 136 creditors - most of which are consumers - roughly 9.2 million pounds ($13 million).
We may never understand Peter Rexstrew's motivation for operating Premier FX in this way, using new customers' funds to pay existing customers or business expenses.
Many staff at financial companies have been working from home since Britain went into its first lockdown in March last year to fight the COVID-19 pandemic.
During this third lockdown, there has been a greater impact on mental well-being, with many people struggling with job security, caring responsibilities, home schooling, bereavements and lockdown fatigue.
Mohammed Zina was employed by Goldman Sachs International as an analyst in the Conflicts Resolution Group in their London office. Suhail Zina was a solicitor at Clifford Chance, also in London.
Goldman Sachs said the protection of confidential client information is of paramount importance for the bank, and it has worked very closely with the FCA.
Some banks and building societies have informed us that they are either going ahead with branch closures already announced, or announcing new branch closures during the current lockdown.
We are concerned that these activities could have significant consequences for customers.